[Bugfix] GR1 V6 Handling duplicate UPN

[dutt0]

Overview/Summary

This Pull Request fixes the issue when there is a duplicate UPN in one of the columns, the user should be directed to review their lists for accuracy instead of going through other conditions for compliance check.

This PR fixes/adds/changes/removes

This PR adds fix for compliant result if

1. duplicate UPN found in highly privileged account list
2. duplicate UPN found in regular account list
3. File doesn't have proper header

Breaking Changes

N/A

Testing Evidence

As part of this Pull Request I have

• Checked for duplicate Pull Requests
• Associated it with relevant GitHub Issues
• Ensured my code/branch is up-to-date with the latest changes in the main branch
• Performed testing and provided evidence.
• Updated relevant and associated documentation.
• Ensure PowerShell module versions have been updated (manually or with the ./tools/Update-ModuleVersions.ps1 script)