remove calls to optional paramaters so that the test is compatible with ruby versions < 2.1
remove calls to optional paramaters so that the test is compatible with ruby versions < 2.1

adelez/grpc,simonkuang/grpc,sreecha/grpc,firebase/grpc,daniel-j-born/grpc,carl-mastrangelo/grpc,vjpai/grpc,carl-mastrangelo/grpc,stanley-cheung/grpc,firebase/grpc,simonkuang/grpc,nicolasnoble/grpc,chrisdunelm/grpc,Crevil/grpc,ncteisen/grpc,ejona86/grpc,jtattermusch/grpc,ncteisen/grpc,jboeuf/grpc,simonkuang/grpc,Crevil/grpc,grpc/grpc,PeterFaiman/ruby-grpc-minimal,ncteisen/grpc,dgquintas/grpc,sreecha/grpc,kumaralokgithub/grpc,daniel-j-born/grpc,ctiller/grpc,vjpai/grpc,adelez/grpc,ctiller/grpc,Vizerai/grpc,donnadionne/grpc,ejona86/grpc,jboeuf/grpc,ctiller/grpc,stanley-cheung/grpc,Vizerai/grpc,vjpai/grpc,deepaklukose/grpc,thinkerou/grpc,Crevil/grpc,fuchsia-mirror/third_party-grpc,mehrdada/grpc,ncteisen/grpc,fuchsia-mirror/third_party-grpc,muxi/grpc,daniel-j-born/grpc,ejona86/grpc,sreecha/grpc,sreecha/grpc,kumaralokgithub/grpc,adelez/grpc,quizlet/grpc,yongni/grpc,grpc/grpc,ncteisen/grpc,Vizerai/grpc,thinkerou/grpc,dgquintas/grpc,kumaralokgithub/grpc,donnadionne/grpc,pszemus/grpc,mehrdada/grpc,jtattermusch/grpc,deepaklukose/grpc,pszemus/grpc,mehrdada/grpc,grpc/grpc,thinkerou/grpc,ctiller/grpc,chrisdunelm/grpc,chrisdunelm/grpc,fuchsia-mirror/third_party-grpc,yongni/grpc,jtattermusch/grpc,jboeuf/grpc,kumaralokgithub/grpc,nicolasnoble/grpc,matt-kwong/grpc,quizlet/grpc,donnadionne/grpc,ncteisen/grpc,geffzhang/grpc,murgatroid99/grpc,murgatroid99/grpc,murgatroid99/grpc,vjpai/grpc,chrisdunelm/grpc,ctiller/grpc,stanley-cheung/grpc,stanley-cheung/grpc,kumaralokgithub/grpc,pszemus/grpc,jboeuf/grpc,kpayson64/grpc,quizlet/grpc,stanley-cheung/grpc,donnadionne/grpc,Vizerai/grpc,carl-mastrangelo/grpc,adelez/grpc,carl-mastrangelo/grpc,fuchsia-mirror/third_party-grpc,dgquintas/grpc,simonkuang/grpc,muxi/grpc,geffzhang/grpc,ejona86/grpc,geffzhang/grpc,Vizerai/grpc,adelez/grpc,deepaklukose/grpc,grpc/grpc,sreecha/grpc,nicolasnoble/grpc,quizlet/grpc,ejona86/grpc,yongni/grpc,sreecha/grpc,quizlet/grpc,jboeuf/grpc,pszemus/grpc,Vizerai/grpc,yongni/grpc,geffzhang/grpc,grpc/grpc,vjpai/grpc,yongni/grpc,deepaklukose/grpc,deepaklukose/grpc,PeterFaiman/ruby-grpc-minimal,nicolasnoble/grpc,daniel-j-born/grpc,murgatroid99/grpc,daniel-j-born/grpc,ejona86/grpc,matt-kwong/grpc,adelez/grpc,nicolasnoble/grpc,thinkerou/grpc,kpayson64/grpc,mehrdada/grpc,grpc/grpc,pszemus/grpc,jboeuf/grpc,ncteisen/grpc,murgatroid99/grpc,vjpai/grpc,firebase/grpc,PeterFaiman/ruby-grpc-minimal,jboeuf/grpc,sreecha/grpc,PeterFaiman/ruby-grpc-minimal,jtattermusch/grpc,jtattermusch/grpc,donnadionne/grpc,donnadionne/grpc,muxi/grpc,jboeuf/grpc,matt-kwong/grpc,stanley-cheung/grpc,chrisdunelm/grpc,nicolasnoble/grpc,firebase/grpc,jboeuf/grpc,grpc/grpc,ncteisen/grpc,matt-kwong/grpc,deepaklukose/grpc,chrisdunelm/grpc,muxi/grpc,jboeuf/grpc,quizlet/grpc,carl-mastrangelo/grpc,kumaralokgithub/grpc,quizlet/grpc,pszemus/grpc,mehrdada/grpc,stanley-cheung/grpc,thinkerou/grpc,ncteisen/grpc,ejona86/grpc,simonkuang/grpc,deepaklukose/grpc,carl-mastrangelo/grpc,mehrdada/grpc,murgatroid99/grpc,stanley-cheung/grpc,yongni/grpc,daniel-j-born/grpc,simonkuang/grpc,fuchsia-mirror/third_party-grpc,Crevil/grpc,thinkerou/grpc,Vizerai/grpc,quizlet/grpc,deepaklukose/grpc,vjpai/grpc,PeterFaiman/ruby-grpc-minimal,vjpai/grpc,dgquintas/grpc,jtattermusch/grpc,mehrdada/grpc,kpayson64/grpc,ctiller/grpc,mehrdada/grpc,stanley-cheung/grpc,PeterFaiman/ruby-grpc-minimal,dgquintas/grpc,kpayson64/grpc,nicolasnoble/grpc,thinkerou/grpc,deepaklukose/grpc,fuchsia-mirror/third_party-grpc,donnadionne/grpc,kpayson64/grpc,matt-kwong/grpc,geffzhang/grpc,matt-kwong/grpc,ncteisen/grpc,kumaralokgithub/grpc,daniel-j-born/grpc,simonkuang/grpc,vjpai/grpc,jtattermusch/grpc,firebase/grpc,kpayson64/grpc,ncteisen/grpc,vjpai/grpc,dgquintas/grpc,kpayson64/grpc,Crevil/grpc,grpc/grpc,carl-mastrangelo/grpc,muxi/grpc,PeterFaiman/ruby-grpc-minimal,jtattermusch/grpc,mehrdada/grpc,PeterFaiman/ruby-grpc-minimal,donnadionne/grpc,adelez/grpc,thinkerou/grpc,stanley-cheung/grpc,chrisdunelm/grpc,stanley-cheung/grpc,carl-mastrangelo/grpc,Crevil/grpc,jboeuf/grpc,stanley-cheung/grpc,nicolasnoble/grpc,muxi/grpc,firebase/grpc,muxi/grpc,daniel-j-born/grpc,murgatroid99/grpc,mehrdada/grpc,dgquintas/grpc,Crevil/grpc,muxi/grpc,simonkuang/grpc,Vizerai/grpc,geffzhang/grpc,murgatroid99/grpc,thinkerou/grpc,donnadionne/grpc,Crevil/grpc,fuchsia-mirror/third_party-grpc,dgquintas/grpc,geffzhang/grpc,firebase/grpc,ctiller/grpc,grpc/grpc,nicolasnoble/grpc,PeterFaiman/ruby-grpc-minimal,jtattermusch/grpc,carl-mastrangelo/grpc,sreecha/grpc,nicolasnoble/grpc,geffzhang/grpc,thinkerou/grpc,ejona86/grpc,donnadionne/grpc,sreecha/grpc,ejona86/grpc,grpc/grpc,ejona86/grpc,kpayson64/grpc,ctiller/grpc,Vizerai/grpc,dgquintas/grpc,quizlet/grpc,pszemus/grpc,fuchsia-mirror/third_party-grpc,firebase/grpc,sreecha/grpc,chrisdunelm/grpc,nicolasnoble/grpc,grpc/grpc,adelez/grpc,firebase/grpc,jtattermusch/grpc,mehrdada/grpc,vjpai/grpc,firebase/grpc,yongni/grpc,geffzhang/grpc,sreecha/grpc,kumaralokgithub/grpc,muxi/grpc,carl-mastrangelo/grpc,dgquintas/grpc,sreecha/grpc,chrisdunelm/grpc,muxi/grpc,chrisdunelm/grpc,murgatroid99/grpc,simonkuang/grpc,jboeuf/grpc,nicolasnoble/grpc,donnadionne/grpc,jtattermusch/grpc,jtattermusch/grpc,Crevil/grpc,chrisdunelm/grpc,vjpai/grpc,yongni/grpc,kumaralokgithub/grpc,matt-kwong/grpc,pszemus/grpc,ejona86/grpc,carl-mastrangelo/grpc,donnadionne/grpc,matt-kwong/grpc,kpayson64/grpc,pszemus/grpc,matt-kwong/grpc,ncteisen/grpc,pszemus/grpc,fuchsia-mirror/third_party-grpc,ctiller/grpc,pszemus/grpc,ctiller/grpc,PeterFaiman/ruby-grpc-minimal,thinkerou/grpc,muxi/grpc,kpayson64/grpc,thinkerou/grpc,carl-mastrangelo/grpc,fuchsia-mirror/third_party-grpc,dgquintas/grpc,muxi/grpc,mehrdada/grpc,ejona86/grpc,ctiller/grpc,grpc/grpc,murgatroid99/grpc,adelez/grpc,Vizerai/grpc,daniel-j-born/grpc,Vizerai/grpc,firebase/grpc,firebase/grpc,yongni/grpc,ctiller/grpc,pszemus/grpc,kpayson64/grpc