[Bug] MetadataStoreTest.emptyStoreTest and testGetChildren methods fail for Zookeeper Metadata Store consistently on first attempt and pass on second try

### Search before asking

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

### Version

master 6ab322ed

### Minimal reproduce step

```
# compile & install core-modules
mvn -Pcore-modules,-main -T 1C clean install -DskipTests -Dspotbugs.skip=true
# run test without retries
mvn -DredirectTestOutputToFile=false -DtestRetryCount=0 test -pl pulsar-metadata -Dtest=MetadataStoreTest
```

### What did you expect to see?

MetadataStoreTest.emptyStoreTest and testGetChildren should pass without retrying.

### What did you see instead?

The tests fail if there's existing state which seems like a bug.

### Anything else?

I think it would be important to understand the reason before releasing so that a possible fix could be included in the next release.

### Are you willing to submit a PR?

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

Start by running the reported Maven setup and MetadataStoreTest in the pulsar-metadata module with retries disabled. Investigate why emptyStoreTest and testGetChildren fail when existing state is present, then verify both tests pass consistently on the first attempt without retries.

Written by the indexing model from the issue text.