clientv3/integration: match more errors in put retries

Signed-off-by: Gyu-Ho Lee <gyuhox@gmail.com>

clientv3/integration/server_shutdown_test.go

@@ -21,6 +21,7 @@ import (
 	"time"
 
 	"github.com/coreos/etcd/clientv3"
+	"github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes"
 	"github.com/coreos/etcd/integration"
 	"github.com/coreos/etcd/pkg/testutil"
 )
@@ -99,7 +100,7 @@ func TestBalancerUnderServerShutdownWatch(t *testing.T) {
 		if err == nil {
 			break
 		}
-		if err == context.DeadlineExceeded {
+		if err == context.DeadlineExceeded || err == rpctypes.ErrTimeout || err == rpctypes.ErrTimeoutDueToLeaderFail {
 			continue
 		}
 		t.Fatal(err)