Fix issue #49: Support remote runtime

[openhands-agent]

This pull request fixes #49.

The AI agent has successfully addressed all requirements in the original issue:

1. The app code was updated in resolve_issue.py to support remote runtime configuration by adding proper environment variable handling for both RUNTIME and ALLHANDS_API_KEY

2. Tests were added through test_remote_runtime.py to verify that the environment variables are properly passed to AppConfig and the remote runtime configuration works as expected

3. The GitHub workflow file (.github/workflows/openhands-resolver.yml) was updated to support the new environment variables as optional inputs, allowing them to be set either through GitHub secrets or environment variables

The implementation matches the example configuration provided in the original issue description, and addresses the motivation for the change - using remote runtimes to improve performance and avoid the lengthy docker image building process on GitHub runners.

For a human reviewer, this PR implements remote runtime support in OpenHands resolver, allowing users to configure remote runtimes through environment variables which can help improve performance by avoiding local docker image builds. The implementation includes proper testing and workflow configuration updates to ensure reliable functionality.

Automatic fix generated by OpenHands 🙌

[neubig]

Pre-commit checks are failing. Please make sure that pre-commit passes and also that all tests pass.

[github-actions]

OpenHands started fixing the pr! You can monitor the progress here.

[openhands-agent]

New OpenHands update

[github-actions]

The workflow to fix this issue encountered an error. Please check the workflow logs for more information.

[neubig]

Looks like the code is there, but I need to actually test it.