private TubeMQResult queryGroupExist(QueryConsumerGroupReq req) {
        if (!req.legal()) {
            return TubeMQResult.errorResult(TubeMQErrorConst.PARAM_ILLEGAL);
        }
        return topicService.queryGroupExist(req);
    }
query group exist
@param req
@return
inlong-tubemq/tubemq-manager/src/main/java/org/apache/inlong/tubemq/manager/controller/group/GroupController.java