Fix issue #331: Disable "github" microagent within github resolver

[openhands-agent]

This pull request fixes #331.

The PR successfully addresses all requirements specified in the issue:

1. The openhands-ai dependency was updated to version 0.13.1 in pyproject.toml
2. The github microagent was properly disabled through configuration in resolve_issue.py using the AgentConfig's disabled_microagents parameter
3. Tests are passing after the changes, including a fix for the MessageAction parameter name

The changes are minimal and focused, addressing the core conflict between the OpenHands github resolver workflow and the github microagent. The implementation correctly uses the new feature from openhands-ai 0.13.1 that allows disabling specific microagents.

Additionally, the bug fix for the MessageAction parameter name (images_urls → image_urls) ensures compatibility with the latest API changes in openhands-ai 0.13.1.

These changes should prevent any workflow conflicts while maintaining all existing functionality.

Automatic fix generated by OpenHands 🙌

[neubig]

This looks good!