disable streaming thread

Author: sakthivelmanii

google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncResultSetImpl.java

@@ -490,7 +490,7 @@ public ApiFuture<Void> setCallback(Executor exec, ReadyCallback cb) {
       this.result = SettableApiFuture.create();
       this.state = State.STREAMING_INITIALIZED;
       initiateProduceRows();
-//      this.service.execute(new InitiateStreamingRunnable());
+      //      this.service.execute(new InitiateStreamingRunnable());
       this.executor = MoreExecutors.newSequentialExecutor(Preconditions.checkNotNull(exec));
       this.callback = Preconditions.checkNotNull(cb);
       pausedLatch.countDown();