Flaky-test: OneWayReplicatorDeduplicationTest.cleanup

### Search before reporting

- [x] I searched in the [issues](https://github.com/apache/pulsar/issues) and found nothing similar.

### Example failure

https://github.com/apache/pulsar/actions/runs/18472389959/job/52629860672#step:11:916

### Exception stacktrace

```text
org.testng.internal.invokers.InvokeMethodRunnable$TestNGRuntimeException: org.apache.pulsar.client.admin.PulsarAdminException: HTTP 422 {}
at org.testng.internal.invokers.InvokeMethodRunnable.runOne(InvokeMethodRunnable.java:56)
at org.testng.internal.invokers.InvokeMethodRunnable.call(InvokeMethodRunnable.java:76)
at org.testng.internal.invokers.InvokeMethodRunnable.call(InvokeMethodRunnable.java:11)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
at java.base/java.lang.Thread.run(Thread.java:1583)
Caused by: org.apache.pulsar.client.admin.PulsarAdminException: HTTP 422 {}
at org.apache.pulsar.client.admin.PulsarAdminException.wrap(PulsarAdminException.java:252)
at org.apache.pulsar.client.admin.internal.BaseResource.sync(BaseResource.java:352)
at org.apache.pulsar.client.admin.internal.NamespacesImpl.deleteNamespace(NamespacesImpl.java:230)
at org.apache.pulsar.broker.service.OneWayReplicatorTestBase.cleanupPulsarResources(OneWayReplicatorTestBase.java:309)
at org.apache.pulsar.broker.service.OneWayReplicatorTestBase.cleanup(OneWayReplicatorTestBase.java:320)
at org.apache.pulsar.broker.service.OneWayReplicatorDeduplicationTest.cleanup(OneWayReplicatorDeduplicationTest.java:109)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at org.testng.internal.invokers.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:139)
at org.testng.internal.invokers.InvokeMethodRunnable.runOne(InvokeMethodRunnable.java:47)
... 6 more
Suppressed: org.apache.pulsar.client.admin.PulsarAdminException: HTTP 422 {}
at org.apache.pulsar.client.admin.internal.BaseResource.getApiException(BaseResource.java:291)
at org.apache.pulsar.client.admin.internal.BaseResource$4.failed(BaseResource.java:237)
at org.glassfish.jersey.client.JerseyInvocation$1.failed(JerseyInvocation.java:898)
at org.glassfish.jersey.client.JerseyInvocation$1.completed(JerseyInvocation.java:879)
at org.glassfish.jersey.client.ClientRuntime.processResponse(ClientRuntime.java:232)
at org.glassfish.jersey.client.ClientRuntime.access$200(ClientRuntime.java:62)
at org.glassfish.jersey.client.ClientRuntime$2.lambda$response$0(ClientRuntime.java:176)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:248)
at org.glassfish.jersey.internal.Errors$1.call(Errors.java:244)
```

### Are you willing to submit a PR?

- [ ] I'm willing to submit a PR!

Start with OneWayReplicatorDeduplicationTest.cleanup and the inherited cleanupPulsarResources and cleanup methods in OneWayReplicatorTestBase.java. Run the affected test and inspect the linked CI failure, focusing on the HTTP 422 from NamespacesImpl.deleteNamespace. Done means the cleanup no longer produces this flaky failure.

Written by the indexing model from the issue text.