public ConcurrentHashMap<String, ConcurrentHashSet<String>> getRegTopicGroupMap() {
        return topicGroupMap;
    }
get all registered topic-group map information

@return the registered topic-group map
inlong-tubemq/tubemq-server/src/main/java/org/apache/inlong/tubemq/server/master/nodemanage/nodeconsumer/ConsumerInfoHolder.java