docs: public synchronized void cleanWaitTaskQueue() {
  
          for (ParallelTask task : waitQ) {
              task.setState(ParallelTaskState.COMPLETED_WITH_ERROR);
              task.getTaskErrorMetas().add(
                      new TaskErrorMeta(TaskErrorType.USER_CANCELED, "NA"));
              logger.info(
                      "task {} removed from wait q. This task has been marked as USER CANCELED.",
                      task.getTaskId());
  
          }
  
          waitQ.clear();
      }