docs: public void sendAllMessage() {
      if (!isConnected()) {
        return;
      }
  
      LOG.info("Flushing all pending data in StreamManagerClient");
      // Collect all tuples in queue
      int size = outStreamQueue.size();
      for (int i = 0; i < size; i++) {
        Message streamMessage = outStreamQueue.poll();
  
        sendMessage(streamMessage);
      }
    }