[fix] [broker] Fix can not subscribe partitioned topic with a suffix-matched regexp

[poorbarcode]

Motivation

If a consumer tries to subscribe to a partitioned topic with a suffix-matched regexp, it does not work.

• create topic persistent://public/default/tp
• create a consumer with regexp persistent://public/default/tp$
• the pattern consumer has no internal consumers.

You can reproduce the issue by the test testPreciseRegexpSubscribe.

• it can work when using 2.10.x
• it can not work when using >=2.11.0, it is a break change due to PIP-145

https://github.com/apache/pulsar/pull/21885 fixed one wrong logic here, but there is still another wrong logic, see https://github.com/apache/pulsar/blob/master/pulsar-broker/src/main/java/org/apache/pulsar/broker/service/TopicListService.java#L64

@Override
public void accept(String topicName, NotificationType notificationType) {
    // The param "topicName" contains the partition suffix, which causes a suffix-matched regexp not to match.
    if (topicsPattern.matcher(topicName).matches()) {
        List<String> newTopics;
        List<String> deletedTopics;
    ...

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Why can the test testPreciseRegexpSubscribe pass?

https://github.com/apache/pulsar/pull/21885 added a test testPreciseRegexpSubscribe that covers the test which creates a consumer with a suffix-matched regexp. It works as below:

• create a consumer with a suffix-matched regexp
• create a partitioned topic
• two events will trigger the pattern consumer to auto-create an internal single partition consumer.
  • Start a new recheckTopicsChangeAfterReconnect after the topic watcher is connected. https://github.com/apache/pulsar/pull/21885 fixed the wrong behavior.
  • Receive an event that a new topic created. Current PR is trying to fix the wrong behavior.

The test testPreciseRegexpSubscribe can not pass as the below flow:

• create a consumer with a suffix-matched regexp
• wait for Topic List Watcher to start.
  • the consumer will call recheckTopicsChangeAfterReconnect at this step.
• create a partitioned topic
  • the consumer can not receive the event due to the wrong logic, then the test failed.

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Modifications

• Review all the codes of the Topic List Watcher and add descriptions of the topic name.
• Fix the wrong behavior.

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Documentation

• [ ] doc
• [ ] doc-required
• [x] doc-not-needed
• [ ] doc-complete

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