Bug 42 (31506) role assignment cleanup

[mbrat2005]

Overview/Summary

Fixes to Role Assignment cleanup, cleanup script

This PR fixes/adds/changes/removes

1. Moved Role Assignment cleanup to Resource Graph, simplifying cleanup query to make it work if Policy Assignments were removed
2. Fixed issue with duplicate resource ID where Resource Graph returns results at parent and child scopes (Get-Unique workaround)
3. Aligned Policy Assignments query with other queries (now that $policyAssignments is unnecessary)

Breaking Changes

1. None

As part of this Pull Request I have

• Read the Contribution Guide and ensured this PR is compliant with the guide
• Checked for duplicate Pull Requests
• Associated it with relevant GitHub Issues or ADO Work Items (Internal Only)
• Ensured my code/branch is up-to-date with the latest changes in the main branch
• Ensured PR tests are passing
• Updated relevant and associated documentation (e.g. Contribution Guide, Docs etc.)

[Brunoga-MS]

Changes LGTM ... I would just put the various select on the same line they should belong to (i.e., instruction on line 104 should be at the end of line 103. Same for line 109, 119, 124, 129

[arjenhuitema]

LGTM. Let me know when it´s ready to merge.

[Brunoga-MS]

@arjenhuitema : ready to be merged on my side