Revert "Fix: File Descriptor leak"

[enyst]

Reverts #6883

Sorry, I can't run main this morning, and the interesting part is that the errors are different for different providers. It must be working fine with Anthropic without proxy (direct API call), but not via litellm_proxy, and with log_completions disabled (I have it enabled).

With Claude, directly

 File "/Users/enyst/repos/odie/openhands/llm/llm.py", line 314, in wrapper
    f.write(json.dumps(_d))
...
  File "/Users/enyst/.pyenv/versions/3.12.6/lib/python3.12/json/encoder.py", line 180, in default
    raise TypeError(f'Object of type {o.__class__.__name__} '
TypeError: Object of type HTTPHandler is not JSON serializable

With Claude, via litellm proxy:

litellm.exceptions.APIError: litellm.APIError: APIError: Litellm_proxyException - 'HTTPHandler' object has no attribute 'api_key'

With o3-mini, directly:

litellm.exceptions.APIError: litellm.APIError: APIError: OpenAIException - 'HTTPHandler' object has no attribute 'api_key'

The first can be fixed by just popping out of kwargs the new client after the call, but the other two are non-obvious to me at first sight, WDYT?

---

To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:bcf7b37-nikolaik   --name openhands-app-bcf7b37   docker.all-hands.dev/all-hands-ai/openhands:bcf7b37

[tofarr]

Ok. We can revisit the fix on Monday