protected void maybeUpdateSubscribedTopicNamesAndGroupSubscriptionType(
        ModernGroupMember oldMember,
        ModernGroupMember newMember
    ) {
        maybeUpdateSubscribedTopicNames(subscribedTopicNames, oldMember, newMember);
        subscriptionType.set(subscriptionType(subscribedTopicNames, members.size()));
    }
Updates the subscribed topic names count.
The subscription type is updated as a consequence.

@param oldMember The old member.
@param newMember The new member.
group-coordinator/src/main/java/org/apache/kafka/coordinator/group/modern/ModernGroup.java