Integrate CISA review feedback into aad baseline

[tkol2022]

🗣 Description

This update includes the following changes to the M365 AAD security configuration baseline:

• Changes to improve overall consistency of format and language throughout
• Grammar and spelling fixes
• Language and verbiage updates for increased reader clarity

This update does NOT include any materially significant changes to the number of or content in policy items in the baseline itself that would require a change in settings to align with the baseline recommendations.

💭 Motivation and context

The updates included further refine and improve the overall readability and clarity of the baseline document. The result should be a baseline that is easier to interpret and use as a reference for M365 tenant administrators.

Closes #532

🧪 Testing

Compare the separately provided Word version with track changes of the AAD baseline document with the changes in the markdown in this branch. Accepted/modified suggested changes as appropriate and mirrored in markdown, rejected and additional changes commented in Word and sync'd to markdown as needed.

Manual review of markdown and ensure that the automated markdown test on the PR passes.

✅ Pre-approval checklist

• This PR has an informative and human-readable title.
• Changes are limited to a single goal - eschew scope creep!
• All future TODOs are captured in issues, which are referenced
  in code comments.
• All relevant type-of-change labels have been added.
• All relevant repo and/or project documentation has been updated
  to reflect the changes in this PR.
• All new and existing tests pass.

✅ Pre-merge checklist

• Rebase the branch against the parent branch prior to merge as needed.
• All CISA feedback has been reviewed and adjudicated successfully

✅ Post-merge checklist

• Confirm that the parent branch passes all tests after the merge

[nanda-katikaneni]

Looks good to most part - commented in-line about a few inconsistencies/mismatches. One comment about Word document: the table of contents need an update, it currently has a weird format.

Will read through the full doc one more time for any additional comments.