private void maybeUpdateServerAssignors(
        ConsumerGroupMember oldMember,
        ConsumerGroupMember newMember
    ) {
        maybeUpdateServerAssignors(serverAssignors, oldMember, newMember);
    }
Updates the server assignors count.

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