@TestOnly
  public void fakeRegister(TriggerInformation triggerInformation, TriggerExecutor triggerExecutor) {
    // register in trigger-table
    triggerTable.addTriggerInformation(triggerInformation.getTriggerName(), triggerInformation);
    // update PatternTreeMap
    patternTreeMap.append(triggerInformation.getPathPattern(), triggerInformation.getTriggerName());
    executorMap.put(triggerInformation.getTriggerName(), triggerExecutor);
  }
Get DataNodeLocation of the given StatefulTrigger.

@param triggerName given trigger
@return TDataNodeLocation of DataNode where instance of given stateful trigger is on. Null if
    trigger not found.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/trigger/service/TriggerManagementService.java