[Bug] Old Engine not killed after deregisterEngine

### Code of Conduct

- [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

### Search before asking

- [x] I have searched in the [issues](https://github.com/apache/kyuubi/issues?q=is%3Aissue) and found no similar issues.

### Describe the bug

Share_Level: Server / Server_Local
The old engine is not responding due to Full GC and is deleted from zookeeper, however the engine itself is not killed. So there are two engines exists

### Affects Version(s)

master

### Kyuubi Server Log Output

```logtalk

```

### Kyuubi Engine Log Output

```logtalk

```

### Kyuubi Server Configurations

```yaml

```

### Kyuubi Engine Configurations

```yaml

```

### Additional context

_No response_

### Are you willing to submit PR?

- [x] Yes. I would be willing to submit a PR with guidance from the Kyuubi community to fix.
- [ ] No. I cannot submit a PR at this time.

Start by locating the deregisterEngine implementation and tracing how engine removal from ZooKeeper relates to process termination. Reproduce the Full GC scenario described in the issue and verify that deregistering an unresponsive old engine kills it, leaving only the replacement engine.

Written by the indexing model from the issue text.