@Override
  public boolean hasRunnables() {
    schedLock();
    try {
      return queueHasRunnables();
    } finally {
      schedUnlock();
    }
  }
Returns true if there are procedures available to process. NOTE: this method is called with the
sched lock held.

@return true if there are procedures available to process, otherwise false.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/procedure/scheduler/AbstractProcedureScheduler.java