GH Workflow update for Policy Testing

[Springstone]

Overview/Summary

Updating portal testing workflow to only test updated or added policies, instead of all policies everytime.

This PR fixes/adds/changes/removes

1. Replace me
2. Replace me
3. Replace me

Breaking Changes

1. N/A

Testing Evidence

Please provide any testing evidence to show that your Pull Request works/fixes as described and planned (include screenshots, if appropriate).

Testing URLs

Azure Public

As part of this Pull Request I have

• Checked for duplicate Pull Requests
• Associated it with relevant issues, for tracking and closure.
• Ensured my code/branch is up-to-date with the latest changes in the main branch
• Performed testing and provided evidence.
• Ensured contribution guidance is followed.
• Updated relevant and associated documentation.
• Updated the "What's New?" wiki page (located: /docs/wiki/whats-new.md)