[test][broker] Reproduce shared topic permission deletion

[mattisonchao]

Motivation

In a multi-cluster deployment with separate local metadata stores and a shared configuration metadata store, topic-level permissions are shared even though topic lifecycles remain local. Deleting a topic in one cluster currently removes the shared permission entry while the same-named topic remains available in another cluster.

This draft adds a deterministic regression reproducer before the behavior is corrected.

Modifications

• Add a two-broker integration test using the existing shared-configuration-store fixture.
• Create the same topic in both clusters, grant topic-level permissions through one cluster, and verify they are visible through the other.
• Delete the topic from one cluster, verify the peer topic still exists, and assert that its permissions remain.

Testing

• gradle :pulsar-broker:checkstyleTest passes.
• gradle :pulsar-broker:test --tests "org.apache.pulsar.broker.service.OneWayReplicatorUsingGlobalZKTest.testDeletingTopicOnOneClusterKeepsSharedTopicPermissions" -PtestRetryCount=0 reproduces the issue: the peer topic remains, but its permissions are {}.