Create hello_world_from_jules.yml workflow

[google-labs-jules]

This pull request introduces a new GitHub Actions workflow file, hello_world_from_jules.yml, as requested. The workflow is configured to trigger on pull_request events, has write-all permissions for the GitHub token, and includes a single job that prints "Hello World" to the console.

Fixes #33

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PR created automatically by Jules for task 11575194396828076864 started by @schcamille

[google-labs-jules]

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