remove useless asyncComplete.

Author: hfutatzhanghb

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/router/async/RouterAsyncClientProtocol.java

@@ -1060,7 +1060,6 @@ public boolean setReplication(String src, short replication)
   @VisibleForTesting
   @Override
   public boolean isMultiDestDirectory(String src) throws IOException {
-    asyncComplete(false);
     asyncTry(() -> {
       if (rpcServer.isPathAll(src)) {
         List<RemoteLocation> locations;