tidb: Clean env when running getExecRet
tidb: Clean env when running getExecRet

mccxj/tidb,zimulala/tidb,Nify/tidb,XuHuaiyu/tidb,EvilMcJerkface/tidb,c4pt0r/tidb,ueizhou/tidb,CodeRushing/tidb,wusphinx/tidb,spongedu/tidb,c4pt0r/tidb,Cofyc/tidb,mccxj/tidb,cosmtrek/tidb,pingcap/tidb,andelf/tidb,ming-relax/tidb,CodeRushing/tidb,astaxie/tidb,ngaut/tidb,8cbx/tidb,kyle-wang/tidb,yuanwhy/tidb,kyle-wang/tidb,c4pt0r/tidb,andelf/tidb,pingcap/tidb,pingcap/tidb,Cofyc/tidb,myrice/tidb,c4pt0r/tidb,pingcap/tidb,cosmtrek/tidb,silentred/tidb,pingcap/tidb,ngaut/tidb,ngaut/tidb,louishust/tidb,c4pt0r/tidb,kyle-wang/tidb,wusphinx/tidb,qhsong/tidb,8cbx/tidb,simon-xia/tidb,yangwenmai/tidb,ueizhou/tidb,coocood/tidb,yangwenmai/tidb,ming-relax/tidb,anywhy/tidb,louishust/tidb,pingcap/tidb,qiuyesuifeng/tidb,simon-xia/tidb,XuHuaiyu/tidb,Nify/tidb,kyle-wang/tidb,EvilMcJerkface/tidb,gaocegege/tidb,spongedu/tidb,anywhy/tidb,c4pt0r/tidb,JinheLin/tidb,tiancaiamao/tidb,liyu4/tidb,JinheLin/tidb,yuanwhy/tidb,astaxie/tidb,silenceper/tidb,ngaut/tidb,tiancaiamao/tidb,silenceper/tidb,zs634134578/tidb,kyle-wang/tidb,myrice/tidb,kyle-wang/tidb,qhsong/tidb,zimulala/tidb,silentred/tidb,ngaut/tidb,zs634134578/tidb,coocood/tidb,liyu4/tidb,gaocegege/tidb,ngaut/tidb,qiuyesuifeng/tidb