clientv3/integration: fix TestKVPutError
clientv3/integration: fix TestKVPutError

Signed-off-by: Gyuho Lee <3454051ee3341eb69bdf6fca40899cdad4d86496@gmail.com>

glevand/coreos--etcd,cockroachdb/etcd,vimalk78/etcd,gyuho/etcd,joshix/etcd,fanminshi/etcd,heyitsanthony/etcd,mqliang/etcd,ajityagaty/etcd,mkumatag/etcd,whuwxl/etcd,etcd-io/etcd,ajityagaty/etcd,gyuho/etcd,coreos/etcd,xiang90/etcd,sebrandon1/etcd,joshix/etcd,mqliang/etcd,cockroachdb/etcd,rnaveiras/etcd,mkumatag/etcd,xiang90/etcd,bdarnell/etcd,coreos/etcd,ajityagaty/etcd,mqliang/etcd,li-ang/etcd,mkumatag/etcd,dannysauer/etcd,glevand/coreos--etcd,lorneli/etcd,etcd-io/etcd,dannysauer/etcd,sinsharat/etcd,li-ang/etcd,bdarnell/etcd,sinsharat/etcd,vimalk78/etcd,bluebreezecf/etcd,lorneli/etcd,rnaveiras/etcd,rnaveiras/etcd,etcd-io/etcd,sebrandon1/etcd,heyitsanthony/etcd,whuwxl/etcd,bluebreezecf/etcd,fanminshi/etcd