[Bug] create producer thread stuck

### Search before asking

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

### Version

pulsar client 3.01.
pulsar broker 3.0.1
puslar proxy 3.0.1

### Minimal reproduce step

It is hard to reproduce

### What did you expect to see?

When you use puslar client to create producer objects synchronously, you can trigger a timeout or other exception normally, rather than the thread staying stuck

### What did you see instead?

Threads keep getting stuck when creating producer objects synchronously using puslar client. To reproduce it, the pulsar cluster is stopped, and a timeout exception is reported when the produce object is created. Therefore, it is not clear how this situation has arisen. At present, it has appeared many times in the production environment.

### Anything else?

_No response_

### Are you willing to submit a PR?

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

Start by investigating synchronous producer creation in the Pulsar client when the cluster is stopped, focusing on the reported timeout and the thread that remains stuck. Use the production behavior and attached screenshot as context; done means producer creation returns a timeout or other exception without leaving the thread blocked.

Written by the indexing model from the issue text.