Fix duplicate policy creation bug & dynamic group compliance

[AlfredSchreuder]

Pull Request (PR) description

• Fix duplicate policy creation bug, when existing policy was found in tenant, still a new policy was created.
• Fix dynamic group compliance, when dynamic group was found, returned incompliant due to empty parameters Members & GroupAsMembers. Edited so that those params are only added to the comparison when it is a static group.

Task list

• Added an entry to the change log under the Unreleased section of the file CHANGELOG.md.
  Entry should say what was changed and how that affects users (if applicable), and
  reference the issue being resolved (if applicable).
• Resource parameter descriptions added/updated in the schema.mof.
• Resource documentation added/updated in README.md.
• Resource settings.json file contains all required permissions.
• Examples appropriately added/updated.
• Unit tests added/updated.
• New/changed code adheres to DSC Community Style Guidelines.

[AlfredSchreuder]

@FabienTschanz New PR according to suggestions: #5536 (comment)

[FabienTschanz]

@AlfredSchreuder Awesome, I like that! Looks good to me, thank you very much for your work.