Created markdown for removed policies for M365

[ahuynhMITRE]

🗣 Description

This PR is to create the standard discontinued policy markdowns that will be utilized across M365 and GWS to track policies that have been discontinued, the date of discontinuation, and rationale behind discontinuation.

💭 Motivation and context

This change is required as a direct result of the conversations surrounding the continuous baseline update process to have a central markdown of removed/discontinued policies. This will remove any clutter in the baselines and assessment results.

closes #1016

🧪 Testing

ensure added markdown does not break current repository

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• PR targets the correct parent branch (e.g., main or release-name) for merge.
• Changes are limited to a single goal - eschew scope creep!
• Changes are sized such that they do not touch excessive number of files.
• All future TODOs are captured in issues, which are referenced in code comments.
• These code changes follow the ScubaGear content style guide.
• Related issues these changes resolve are linked preferably via closing keywords.
• All relevant type-of-change labels added.
• All relevant project fields are set.
• All relevant repo and/or project documentation updated to reflect these changes.
• Unit tests added/updated to cover PowerShell and Rego changes.
• Functional tests added/updated to cover PowerShell and Rego changes.
• All relevant functional tests passed.
• All automated checks (e.g., linting, static analysis, unit/smoke tests) passed.

✅ Pre-merge checklist

• PR passed smoke test check.

• Feature branch has been rebased against changes from parent branch, as needed

  Use Rebase branch button below or use this reference to rebase from the command line.

• Resolved all merge conflicts on branch

• Notified merge coordinator that PR is ready for merge via comment mention

✅ Post-merge checklist

• Feature branch deleted after merge to clean up repository.
• Verified that all checks pass on parent branch (e.g., main or release-name) after merge.

[adhilto]

A couple things to think about:

[adhilto]

I would also recommend we edit the baselines/README.md file to include a pointer to this new file.

[ahuynhMITRE]

I would also recommend we edit the baselines/README.md file to include a pointer to this new file.

good catch, will update!

[mitchelbaker-cisa]

Looks great!

[ahuynhMITRE]

@nanda-katikaneni good to merge