ci: DO NOT MERGE - Test to showcase feasibility of validation on PR

[eriqua]

Description

This PR validates the feasibility of a workflow running on pull_request to check if the modules updated by the PR are onboarded to MAR. Workflow structure:

1. Detects the list of changed modules

   Note: this is currently done by an external action, we may want to develop our logic

2. Retrieves the list of onboarded modules

   Note: this is temporarily done using the list of modules in the avm index csv, it will change once the actual list of onboarded modules is available in AVM

3. Checks the list of changed modules against the list of onboarded modules.
4. Fails if one of the changed modules is not found in the list of onboarded modules

Test invalid PR eriqua#27

Test valid PR eriqua#26

Pipeline Reference

Pipeline

Type of Change

• Azure Verified Module updates:
  • Bugfix containing backwards-compatible bug fixes, and I have NOT bumped the MAJOR or MINOR version in version.json:
  • Feature update backwards compatible feature updates, and I have bumped the MINOR version in version.json.
  • Breaking changes and I have bumped the MAJOR version in version.json.
  • Update to documentation
• Update to CI Environment or utilities (Non-module affecting changes)

Checklist

• I'm sure there are no other open Pull Requests for the same update/change
• I have run Set-AVMModule locally to generate the supporting module files.
• My corresponding pipelines / checks run clean and green without any errors or warnings
• I have updated the module's CHANGELOG.md file with an entry for the next version