Add subscribePattern integration tests for subsequent subscription

Extend test coverage to validate subsequent subscriptions (require in-flight coordinator fix for removing regexes https://github.com/apache/kafka/pull/17976) 

https://github.com/apache/kafka/pull/17964#discussion_r1863578362