Add GitHub CI to template source

[evilkermit]

Summary of Changes

Adding .github/workflows and a question to the template that allows the developer to set a new git remote.

I tested by running a copier update on CrystalPilot to ensure that it produced correct output when overriding the git remote.

Checklist

• The PR has a clear and concise title
• Code is self-documented and follows style guidelines.
• Automated tests are written and pass successfully.
• Regression tests (e.g. manually triggered system tests, manual GUI/tool tests, ...) are performed to make sure the PR does not break anything (when applicable)
• Readme file is present and up-to-date.

Documentation Updates

Additional Notes