clientv3/integration: close active connection to get ErrClientConnClosing
clientv3/integration: close active connection to get ErrClientConnClosing

because clientv3.Close won't trigger it any more

clientv3.Close just closes watch client
instead of closing grpc connection

xiang90/etcd,cockroachdb/etcd,mqliang/etcd,mickep76/etcd,OyTao/etcd_learning,whuwxl/etcd,CrazyJvm/etcd,ajityagaty/etcd,bdarnell/etcd,rchicoli/etcd,insequent/etcd,heyitsanthony/etcd,a-robinson/etcd,sinsharat/etcd,sinsharat/etcd,plasticbox/etcd,gyuho/etcd,whuwxl/etcd,hongchaodeng/etcd,lorneli/etcd,dannysauer/etcd,coreos/etcd,rnaveiras/etcd,coreos/etcd,etcd-io/etcd,jlamillan/etcd,bluebreezecf/etcd,YuleiXiao/etcd,li-ang/etcd,mkumatag/etcd,lumjjb/etcd,handsomesun/etcd,hongchaodeng/etcd,fanminshi/etcd,OyTao/etcd_learning,YuleiXiao/etcd,sebrandon1/etcd,endocode/etcd,visheshnp/etcd,sebrandon1/etcd,vimalk78/etcd,bluebreezecf/etcd,gyuho/etcd,lorneli/etcd,CrazyJvm/etcd,xiang90/etcd,fanminshi/etcd,armstrongli/etcd,joshix/etcd,akauppi/etcd,ajityagaty/etcd,endocode/etcd,vimalk78/etcd,mqliang/etcd,yudai/etcd,armstrongli/etcd,joshix/etcd,insequent/etcd,qqsun8819/etcd,a-robinson/etcd,akauppi/etcd,dannysauer/etcd,bdarnell/etcd,mkumatag/etcd,cockroachdb/etcd,lumjjb/etcd,rnaveiras/etcd,qqsun8819/etcd,tguangch/etcd,jlamillan/etcd,ravigadde/etcd,handsomesun/etcd,heyitsanthony/etcd,plasticbox/etcd,etcd-io/etcd,etcd-io/etcd,mkumatag/etcd,glevand/coreos--etcd,tguangch/etcd,yudai/etcd,li-ang/etcd,mqliang/etcd,glevand/coreos--etcd,mickep76/etcd,visheshnp/etcd,rnaveiras/etcd,rchicoli/etcd,ravigadde/etcd,ajityagaty/etcd