code: public static MessageDto askTransactionState(String groupId, String unitId) {
          MessageDto messageDto = new MessageDto();
          messageDto.setGroupId(groupId);
          messageDto.setAction(MessageConstants.ACTION_ASK_TRANSACTION_STATE);
          messageDto.setData(new AskTransactionStateParams(groupId, unitId));
          return messageDto;
      }
docs: 询问事务状态指令
  
  @param groupId groupId
  @param unitId  unitId
  @return MessageDto