Add markdownlint as a pytool plugin [Rebase & FF]

[kenlautner]

Description

Cherry-pick commits that add markdownlint as a pytool plugin as well as markdown fixes in several MD files.
Commits from 202311 included here:

df8805c
6d509b2
72f4ac0
40da3f2
984dee9
c149b3f
aa5ae2a
26eb685
26e38dc

• Impacts functionality?
  • Functionality - Does the change ultimately impact how firmware functions?
  • Examples: Add a new library, publish a new PPI, update an algorithm, ...
• Impacts security?
  • Security - Does the change have a direct security impact on an application,
    flow, or firmware?
  • Examples: Crypto algorithm change, buffer overflow fix, parameter
    validation improvement, ...
• Breaking change?
  • Breaking change - Will anyone consuming this change experience a break
    in build or boot behavior?
  • Examples: Add a new library class, move a module to a different repo, call
    a function in a new library class in a pre-existing module, ...
• Includes tests?
  • Tests - Does the change include any explicit test code?
  • Examples: Unit tests, integration tests, robot tests, ...
• Includes documentation?
  • Documentation - Does the change contain explicit documentation additions
    outside direct code modifications (and comments)?
  • Examples: Update readme file, add feature readme file, link to documentation
    on an a separate Web page, ...

How This Was Tested

N/A

Integration Instructions

N/A

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release/202405@41f41fc). Learn more about missing BASE report.

Additional details and impacted files

@@                Coverage Diff                @@
##             release/202405     #928   +/-   ##
=================================================
  Coverage                  ?    1.25%           
=================================================
  Files                     ?     1424           
  Lines                     ?   358662           
  Branches                  ?     4391           
=================================================
  Hits                      ?     4495           
  Misses                    ?   354106           
  Partials                  ?       61           

Flag	Coverage Δ
MdeModulePkg	0.24% <ø> (?)
MdePkg	5.41% <ø> (?)
NetworkPkg	0.55% <ø> (?)
UefiCpuPkg	4.80% <ø> (?)

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