[SPARKR][TEST] remove unnecessary suppressWarnings
[SPARKR][TEST] remove unnecessary suppressWarnings

## What changes were proposed in this pull request?

In test_mllib.R, there are two unnecessary suppressWarnings. This PR just removes them.

## How was this patch tested?

Existing unit tests.

Author: wm624@hotmail.com <wm624@hotmail.com>

Closes #15697 from wangmiao1981/rtest.

brad-kaiser/spark,map222/spark,nilsgrabbert/spark,jrshust/spark,someorz/spark,icexelloss/spark,shubhamchopra/spark,rikima/spark,brad-kaiser/spark,vinodkc/spark,JoshRosen/spark,kevinyu98/spark,saturday-shi/spark,jrshust/spark,ptkool/spark,skonto/spark,rednaxelafx/apache-spark,wangmiao1981/spark,adrian-ionescu/apache-spark,rekhajoshm/spark,mdespriee/spark,debugger87/spark,setjet/spark,rekhajoshm/spark,adrian-ionescu/apache-spark,joseph-torres/spark,wangmiao1981/spark,gengliangwang/spark,milliman/spark,hvanhovell/spark,sachintyagi22/spark,SHASHANKB/spark,aokolnychyi/spark,wzhfy/spark,byakuinss/spark,jkbradley/spark,aray/spark,hhbyyh/spark,bravo-zhang/spark,JoshRosen/spark,someorz/spark,zuotingbing/spark,ahnqirage/spark,caneGuy/spark,akopich/spark,tengpeng/spark,MLnick/spark,LantaoJin/spark,icexelloss/spark,poffuomo/spark,jianran/spark,gengliangwang/spark,WeichenXu123/spark,aosagie/spark,srowen/spark,xuanyuanking/spark,Aegeaner/spark,zero323/spark,jiangxb1987/spark,liutang123/spark,witgo/spark,caneGuy/spark,taroplus/spark,UndeadBaneGitHub/spark,zzcclp/spark,publicRoman/spark,BryanCutler/spark,actuaryzhang/spark,lvdongr/spark,aokolnychyi/spark,narahari92/spark,byakuinss/spark,minixalpha/spark,ddna1021/spark,spark-test/spark,ahnqirage/spark,setjet/spark,eyalfa/spark,highfei2011/spark,BryanCutler/spark,szhem/spark,witgo/spark,sahilTakiar/spark,zhouyejoe/spark,spark-test/spark,stanzhai/spark,milliman/spark,facaiy/spark,sureshthalamati/spark,spark-test/spark,lvdongr/spark,ddna1021/spark,publicRoman/spark,michalsenkyr/spark,poffuomo/spark,UndeadBaneGitHub/spark,milliman/spark,xflin/spark,MLnick/spark,rikima/spark,ericvandenbergfb/spark,jiangxb1987/spark,1haodian/spark,BryanCutler/spark,chuckchen/spark,lxsmnv/spark,darionyaphet/spark,ahnqirage/spark,xflin/spark,esi-mineset/spark,cin/spark,saltstar/spark,cin/spark,actuaryzhang/spark,huang1900/spark,markhamstra/spark,highfei2011/spark,nilsgrabbert/spark,ddna1021/spark,WeichenXu123/spark,zzcclp/spark,sureshthalamati/spark,shuangshuangwang/spark,huang1900/spark,jkbradley/spark,ioana-delaney/spark,saltstar/spark,sahilTakiar/spark,rikima/spark,jkbradley/spark,darionyaphet/spark,1haodian/spark,mdespriee/spark,debugger87/spark,alunarbeach/spark,SHASHANKB/spark,ConeyLiu/spark,zero323/spark,UndeadBaneGitHub/spark,taroplus/spark,icexelloss/spark,ueshin/apache-spark,szhem/spark,WindCanDie/spark,nchammas/spark,ptkool/spark,janewangfb/spark,cin/spark,zhouyejoe/spark,srowen/spark,nilsgrabbert/spark,stanzhai/spark,zuotingbing/spark,ConeyLiu/spark,wangyum/spark,tengpeng/spark,HyukjinKwon/spark,sureshthalamati/spark,WeichenXu123/spark,sahilTakiar/spark,apache/spark,chuckchen/spark,liyichao/spark,someorz/spark,ueshin/apache-spark,apache-spark-on-k8s/spark,nchammas/spark,bravo-zhang/spark,mdespriee/spark,narahari92/spark,saturday-shi/spark,poffuomo/spark,tejasapatil/spark,caneGuy/spark,holdenk/spark,zzcclp/spark,maropu/spark,nilsgrabbert/spark,gengliangwang/spark,milliman/spark,sureshthalamati/spark,saltstar/spark,ron8hu/spark,xflin/spark,JoshRosen/spark,liutang123/spark,WindCanDie/spark,ddna1021/spark,bOOm-X/spark,vinodkc/spark,nlalevee/spark,akopich/spark,patrick-nicholson/spark,jkbradley/spark,patrick-nicholson/spark,WindCanDie/spark,apache/spark,aosagie/spark,janewangfb/spark,tejasapatil/spark,xuanyuanking/spark,saturday-shi/spark,wangmiao1981/spark,bOOm-X/spark,UndeadBaneGitHub/spark,guoxiaolongzte/spark,1haodian/spark,wangmiao1981/spark,zero323/spark,kissmetrics/spark,mahak/spark,hvanhovell/spark,darionyaphet/spark,pgandhi999/spark,hhbyyh/spark,icexelloss/spark,zzcclp/spark,szhem/spark,holdenk/spark,sachintyagi22/spark,mzl9039/spark,maropu/spark,mike0sv/spark,bdrillard/spark,setjet/spark,mdespriee/spark,mahak/spark,ioana-delaney/spark,hhbyyh/spark,aokolnychyi/spark,apache-spark-on-k8s/spark,patrick-nicholson/spark,eyalfa/spark,debugger87/spark,aosagie/spark,andrewor14/spark,esi-mineset/spark,wzhfy/spark,alunarbeach/spark,someorz/spark,BryanCutler/spark,spark-test/spark,srowen/spark,WindCanDie/spark,ericvandenbergfb/spark,jlopezmalla/spark,szhem/spark,goldmedal/spark,facaiy/spark,JerryLead/spark,stanzhai/spark,esi-mineset/spark,shubhamchopra/spark,MLnick/spark,saltstar/spark,skonto/spark,techaddict/spark,cloud-fan/spark,wangyum/spark,aosagie/spark,actuaryzhang/spark,rekhajoshm/spark,milliman/spark,nchammas/spark,minixalpha/spark,janewangfb/spark,witgo/spark,skonto/spark,liutang123/spark,yanboliang/spark,lxsmnv/spark,matthewfranglen/spark,jiangxb1987/spark,sachintyagi22/spark,JerryLead/spark,akopich/spark,narahari92/spark,zuotingbing/spark,nchammas/spark,sureshthalamati/spark,xflin/spark,zhouyejoe/spark,cloud-fan/spark,jkbradley/spark,hvanhovell/spark,map222/spark,Aegeaner/spark,WeichenXu123/spark,actuaryzhang/spark,sureshthalamati/spark,rekhajoshm/spark,someorz/spark,milliman/spark,mzl9039/spark,aray/spark,vinodkc/spark,bOOm-X/spark,MLnick/spark,hhbyyh/spark,nchammas/spark,actuaryzhang/spark,ericvandenbergfb/spark,liyichao/spark,gengliangwang/spark,bravo-zhang/spark,facaiy/spark,srowen/spark,rikima/spark,shaneknapp/spark,kevinyu98/spark,vinodkc/spark,mike0sv/spark,rednaxelafx/apache-spark,facaiy/spark,BryanCutler/spark,SHASHANKB/spark,lxsmnv/spark,JoshRosen/spark,WeichenXu123/spark,xuanyuanking/spark,hhbyyh/spark,liyichao/spark,liutang123/spark,hhbyyh/spark,MLnick/spark,zuotingbing/spark,HyukjinKwon/spark,liutang123/spark,panfengfeng/spark,kiszk/spark,facaiy/spark,ConeyLiu/spark,markhamstra/spark,ron8hu/spark,rikima/spark,dongjoon-hyun/spark,minixalpha/spark,UndeadBaneGitHub/spark,zero323/spark,kevinyu98/spark,ericvandenbergfb/spark,skonto/spark,wangyum/spark,dhruve/spark,alunarbeach/spark,adrian-ionescu/apache-spark,Aegeaner/spark,darionyaphet/spark,map222/spark,SHASHANKB/spark,lvdongr/spark,apache-spark-on-k8s/spark,bdrillard/spark,kevinyu98/spark,lvdongr/spark,cin/spark,narahari92/spark,ahnqirage/spark,bravo-zhang/spark,minixalpha/spark,rezasafi/spark,lxsmnv/spark,tejasapatil/spark,ConeyLiu/spark,ueshin/apache-spark,liyichao/spark,witgo/spark,markhamstra/spark,loneknightpy/spark,dbtsai/spark,pgandhi999/spark,dhruve/spark,dongjoon-hyun/spark,rezasafi/spark,guoxiaolongzte/spark,goldmedal/spark,jianran/spark,adrian-ionescu/apache-spark,michalsenkyr/spark,alunarbeach/spark,shubhamchopra/spark,tengpeng/spark,eyalfa/spark,SHASHANKB/spark,dbtsai/spark,rezasafi/spark,MLnick/spark,ajaysaini725/spark,dbtsai/spark,JerryLead/spark,loneknightpy/spark,rednaxelafx/apache-spark,liyichao/spark,mzl9039/spark,dhruve/spark,bdrillard/spark,pgandhi999/spark,ajaysaini725/spark,LantaoJin/spark,setjet/spark,ConeyLiu/spark,techaddict/spark,xflin/spark,debugger87/spark,zero323/spark,nlalevee/spark,xuanyuanking/spark,maropu/spark,rednaxelafx/apache-spark,ajaysaini725/spark,ahnqirage/spark,apache/spark,vinodkc/spark,poffuomo/spark,mzl9039/spark,sahilTakiar/spark,jlopezmalla/spark,apache/spark,kissmetrics/spark,joseph-torres/spark,dhruve/spark,liutang123/spark,dhruve/spark,poffuomo/spark,srowen/spark,mahak/spark,loneknightpy/spark,jlopezmalla/spark,hvanhovell/spark,witgo/spark,ConeyLiu/spark,skonto/spark,sachintyagi22/spark,mdespriee/spark,nchammas/spark,tengpeng/spark,tejasapatil/spark,esi-mineset/spark,byakuinss/spark,gengliangwang/spark,Aegeaner/spark,brad-kaiser/spark,chuckchen/spark,UndeadBaneGitHub/spark,janewangfb/spark,ron8hu/spark,dbtsai/spark,eyalfa/spark,icexelloss/spark,cloud-fan/spark,ericvandenbergfb/spark,jrshust/spark,goldmedal/spark,andrewor14/spark,SHASHANKB/spark,caneGuy/spark,stanzhai/spark,publicRoman/spark,skonto/spark,ahnqirage/spark,zero323/spark,apache/spark,liutang123/spark,JerryLead/spark,shuangshuangwang/spark,jkbradley/spark,akopich/spark,JerryLead/spark,ajaysaini725/spark,rekhajoshm/spark,map222/spark,yanboliang/spark,brad-kaiser/spark,taroplus/spark,ron8hu/spark,ron8hu/spark,sahilTakiar/spark,adrian-ionescu/apache-spark,debugger87/spark,eyalfa/spark,kevinyu98/spark,witgo/spark,kiszk/spark,lvdongr/spark,skonto/spark,ericvandenbergfb/spark,joseph-torres/spark,BryanCutler/spark,byakuinss/spark,LantaoJin/spark,saturday-shi/spark,taroplus/spark,bdrillard/spark,ahnqirage/spark,aokolnychyi/spark,nlalevee/spark,publicRoman/spark,loneknightpy/spark,kiszk/spark,hhbyyh/spark,pgandhi999/spark,aray/spark,minixalpha/spark,holdenk/spark,joseph-torres/spark,lxsmnv/spark,guoxiaolongzte/spark,rezasafi/spark,techaddict/spark,techaddict/spark,aosagie/spark,michalsenkyr/spark,ptkool/spark,BryanCutler/spark,zzcclp/spark,markhamstra/spark,WeichenXu123/spark,gengliangwang/spark,dongjoon-hyun/spark,dhruve/spark,saturday-shi/spark,apache-spark-on-k8s/spark,esi-mineset/spark,zuotingbing/spark,map222/spark,darionyaphet/spark,ptkool/spark,kiszk/spark,wzhfy/spark,yanboliang/spark,cloud-fan/spark,vinodkc/spark,rezasafi/spark,liyichao/spark,ueshin/apache-spark,taroplus/spark,bravo-zhang/spark,rednaxelafx/apache-spark,icexelloss/spark,xflin/spark,aokolnychyi/spark,shaneknapp/spark,cloud-fan/spark,chuckchen/spark,nchammas/spark,caneGuy/spark,pgandhi999/spark,andrewor14/spark,JoshRosen/spark,bravo-zhang/spark,shubhamchopra/spark,huang1900/spark,mike0sv/spark,facaiy/spark,andrewor14/spark,jlopezmalla/spark,ddna1021/spark,setjet/spark,yanboliang/spark,markhamstra/spark,huang1900/spark,xuanyuanking/spark,sachintyagi22/spark,rekhajoshm/spark,dhruve/spark,techaddict/spark,brad-kaiser/spark,zuotingbing/spark,techaddict/spark,zuotingbing/spark,ron8hu/spark,janewangfb/spark,zhouyejoe/spark,techaddict/spark,holdenk/spark,pgandhi999/spark,tengpeng/spark,bOOm-X/spark,panfengfeng/spark,panfengfeng/spark,aokolnychyi/spark,huang1900/spark,shaneknapp/spark,xflin/spark,bOOm-X/spark,yanboliang/spark,patrick-nicholson/spark,janewangfb/spark,michalsenkyr/spark,xuanyuanking/spark,WindCanDie/spark,andrewor14/spark,narahari92/spark,jianran/spark,goldmedal/spark,bdrillard/spark,setjet/spark,mahak/spark,WindCanDie/spark,mdespriee/spark,bdrillard/spark,kissmetrics/spark,narahari92/spark,poffuomo/spark,spark-test/spark,dbtsai/spark,darionyaphet/spark,wzhfy/spark,alunarbeach/spark,wangyum/spark,markhamstra/spark,rikima/spark,tejasapatil/spark,joseph-torres/spark,minixalpha/spark,jiangxb1987/spark,mahak/spark,cin/spark,nlalevee/spark,ddna1021/spark,taroplus/spark,patrick-nicholson/spark,wangyum/spark,1haodian/spark,shaneknapp/spark,adrian-ionescu/apache-spark,michalsenkyr/spark,szhem/spark,nilsgrabbert/spark,saturday-shi/spark,loneknightpy/spark,rezasafi/spark,maropu/spark,jiangxb1987/spark,Aegeaner/spark,xuanyuanking/spark,loneknightpy/spark,WindCanDie/spark,poffuomo/spark,kissmetrics/spark,dbtsai/spark,markhamstra/spark,MLnick/spark,caneGuy/spark,janewangfb/spark,LantaoJin/spark,alunarbeach/spark,ioana-delaney/spark,bOOm-X/spark,jiangxb1987/spark,ueshin/apache-spark,sahilTakiar/spark,aokolnychyi/spark,Aegeaner/spark,kevinyu98/spark,tengpeng/spark,wzhfy/spark,loneknightpy/spark,debugger87/spark,chuckchen/spark,wzhfy/spark,mike0sv/spark,hvanhovell/spark,kissmetrics/spark,michalsenkyr/spark,darionyaphet/spark,dongjoon-hyun/spark,michalsenkyr/spark,hvanhovell/spark,highfei2011/spark,nlalevee/spark,ptkool/spark,aray/spark,LantaoJin/spark,guoxiaolongzte/spark,wangmiao1981/spark,dongjoon-hyun/spark,JoshRosen/spark,mahak/spark,ajaysaini725/spark,highfei2011/spark,panfengfeng/spark,map222/spark,aosagie/spark,ptkool/spark,1haodian/spark,facaiy/spark,jianran/spark,alunarbeach/spark,liyichao/spark,HyukjinKwon/spark,kissmetrics/spark,actuaryzhang/spark,JerryLead/spark,maropu/spark,rezasafi/spark,goldmedal/spark,esi-mineset/spark,ioana-delaney/spark,jianran/spark,saltstar/spark,minixalpha/spark,apache-spark-on-k8s/spark,tengpeng/spark,ericvandenbergfb/spark,taroplus/spark,huang1900/spark,bOOm-X/spark,mike0sv/spark,SHASHANKB/spark,rednaxelafx/apache-spark,nlalevee/spark,bravo-zhang/spark,debugger87/spark,rikima/spark,srowen/spark,jianran/spark,yanboliang/spark,wzhfy/spark,goldmedal/spark,nilsgrabbert/spark,holdenk/spark,akopich/spark,wangyum/spark,highfei2011/spark,guoxiaolongzte/spark,jrshust/spark,shubhamchopra/spark,dbtsai/spark,ioana-delaney/spark,zhouyejoe/spark,ajaysaini725/spark,kiszk/spark,lxsmnv/spark,holdenk/spark,dongjoon-hyun/spark,shaneknapp/spark,stanzhai/spark,szhem/spark,maropu/spark,tejasapatil/spark,stanzhai/spark,jlopezmalla/spark,maropu/spark,ron8hu/spark,bdrillard/spark,dongjoon-hyun/spark,shuangshuangwang/spark,andrewor14/spark,sachintyagi22/spark,chuckchen/spark,zzcclp/spark,saltstar/spark,panfengfeng/spark,gengliangwang/spark,eyalfa/spark,actuaryzhang/spark,mdespriee/spark,map222/spark,vinodkc/spark,icexelloss/spark,shaneknapp/spark,cin/spark,huang1900/spark,brad-kaiser/spark,publicRoman/spark,guoxiaolongzte/spark,sahilTakiar/spark,LantaoJin/spark,zhouyejoe/spark,szhem/spark,kissmetrics/spark,shuangshuangwang/spark,mike0sv/spark,ddna1021/spark,kiszk/spark,esi-mineset/spark,JerryLead/spark,rekhajoshm/spark,nlalevee/spark,shubhamchopra/spark,mzl9039/spark,aray/spark,kiszk/spark,narahari92/spark,pgandhi999/spark,sureshthalamati/spark,caneGuy/spark,yanboliang/spark,akopich/spark,wangmiao1981/spark,zhouyejoe/spark,lvdongr/spark,rednaxelafx/apache-spark,zero323/spark,chuckchen/spark,publicRoman/spark,someorz/spark,1haodian/spark,panfengfeng/spark,ueshin/apache-spark,aray/spark,milliman/spark,lxsmnv/spark,apache-spark-on-k8s/spark,highfei2011/spark,shubhamchopra/spark,jkbradley/spark,jlopezmalla/spark,apache/spark,jiangxb1987/spark,jrshust/spark,byakuinss/spark,wangyum/spark,cin/spark,andrewor14/spark,spark-test/spark,adrian-ionescu/apache-spark,sachintyagi22/spark,srowen/spark,ConeyLiu/spark,JoshRosen/spark,kevinyu98/spark,WeichenXu123/spark,ajaysaini725/spark,aosagie/spark,UndeadBaneGitHub/spark,LantaoJin/spark,zzcclp/spark,patrick-nicholson/spark,byakuinss/spark,HyukjinKwon/spark,highfei2011/spark,publicRoman/spark,lvdongr/spark,eyalfa/spark,stanzhai/spark,ueshin/apache-spark,brad-kaiser/spark,mike0sv/spark,shaneknapp/spark,ioana-delaney/spark,mzl9039/spark,goldmedal/spark,saltstar/spark,nilsgrabbert/spark,ptkool/spark,HyukjinKwon/spark,aray/spark,cloud-fan/spark,HyukjinKwon/spark,cloud-fan/spark,apache-spark-on-k8s/spark,hvanhovell/spark,patrick-nicholson/spark,tejasapatil/spark,spark-test/spark,byakuinss/spark,mzl9039/spark,Aegeaner/spark,jianran/spark,HyukjinKwon/spark,shuangshuangwang/spark,jlopezmalla/spark,panfengfeng/spark,shuangshuangwang/spark,saturday-shi/spark,wangmiao1981/spark,guoxiaolongzte/spark,holdenk/spark,mahak/spark,jrshust/spark,someorz/spark,joseph-torres/spark,1haodian/spark,akopich/spark,ioana-delaney/spark,witgo/spark,setjet/spark,apache/spark,shuangshuangwang/spark,jrshust/spark,joseph-torres/spark