Hi all I would like to start a discussion to cherry-pick PIP-321 into `branch-3.0` and `branch-3.3` - https://github.com/apache/pulsar/pull/22378
This PIP Introduced `allowed-clusters` at the namespace level to address if replication is only enabled at the topic level, the replicator will connect fail when creating a producer issue. I want to cherry-pick it into the version `3.0.x` and `3.3.x`. The thread will remain in the open state for 48 hours. If there is no objection, I will perform the cherry-picking. Thanks Kai
