Issue: Cannot disable langsmith pytest plugin

Running this command has no effect
```sh
pytest test.py -p no:langsmith 
```

```
platform linux -- Python 3.12.3, pytest-8.3.5, pluggy-1.5.0
rootdir: 
configfile: pyproject.toml
plugins: cov-6.1.1, langsmith-0.3.41, socket-0.7.0, timeout-2.3.1, fail-slow-0.6.0
timeout: 60.0s
timeout method: signal
timeout func_only: False
collected 0 items    
```


### Suggestion:

Support `-p no:langsmith `