[fix][test] Fix flaky AdminApiTest.partitionedTopicsCursorReset

[lhotari]

Motivation

AdminApiTest.partitionedTopicsCursorReset is flaky in CI. Recent example: PR #25844 run 26175306430 job 77005757000.

Gradle suite > Gradle test > org.apache.pulsar.broker.admin.AdminApiTest > partitionedTopicsCursorReset[2](topic_+&*%{}() \$@#^%) FAILED
    org.apache.pulsar.client.admin.PulsarAdminException$PreconditionFailedException: Subscription has active connected consumers
        at org.apache.pulsar.broker.admin.AdminApiTest.partitionedTopicsCursorReset(AdminApiTest.java:3104)

        Caused by:
        javax.ws.rs.ClientErrorException: HTTP 412 {"reason":"Subscription has active connected consumers"}

consumer.close() returns once the close request has been dispatched to the broker, but the broker may not yet have processed the disconnect when the test immediately calls admin.topics().deleteSubscription(...). The broker's precondition check still sees a connected consumer and returns HTTP 412.

Modifications

Wrap the deleteSubscription call in Awaitility.await().ignoreExceptionsInstanceOf(PreconditionFailedException.class).untilAsserted(...) so the test retries the delete until the broker has detected the consumer disconnect.

Verifying this change

• Make sure that the change passes the CI checks.

This change is already covered by existing tests, such as the modified partitionedTopicsCursorReset test itself.