🧪 Add unit tests for GithubReleaseModuleCommand

[juzaweb]

🎯 What: The testing gap addressed is the lack of test coverage for the GithubReleaseModuleCommand's main handle() method, which runs local git processes and external HTTP requests.

📊 Coverage: Three main scenarios are now covered:

1. Nothing to release: Checks how the command behaves when git log returns no output.
2. Release with changelog: The default happy-path scenario where a changelog is parsed, a file is written/prepended, git add/commit/push is simulated, and a release is posted to the GitHub API.
3. Release without changelog: The --changelog=false flag scenario, which skips file writing and commits, but still successfully posts to the GitHub API.

✨ Result: A significant improvement in test coverage and reliability. The handle method is fully verified without requiring real, destructive Git operations or actual external API requests, preventing unexpected failures during automated testing.

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PR created automatically by Jules for task 18309950654553099013 started by @juzaweb

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