chore(root): add eslint a11y plugin

[evenstensberg]

Describe your changes:

Adds a11y to eslint

• [Build] Implement a11y linting to detect violations #7915

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• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Is this a notable change that will require a special callout in the release notes? For example, will this break compatibility with existing APIs or projects that consume these plugins?

Author Checklist

• Changes address original issue?
• Tests included and/or updated with changes?
• Has this been smoke tested?
• Have you associated this PR with a type: label? Note: this is not necessarily the same as the original issue.
• Have you associated a milestone with this PR? Note: leave blank if unsure.
• Testing instructions included in associated issue OR is this a dependency/testcase change?

Reviewer Checklist

• Changes appear to address issue?
• Reviewer has tested changes by following the provided instructions?
• Changes appear not to be breaking changes?
• Appropriate automated tests included?
• Code style and in-line documentation are appropriate?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 57.43%. Comparing base (2010f2e) to head (0052e6c).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7917      +/-   ##
==========================================
- Coverage   57.66%   57.43%   -0.24%     
==========================================
  Files         677      677              
  Lines       27373    27373              
  Branches     2689     2689              
==========================================
- Hits        15786    15723      -63     
- Misses      11248    11309      +61     
- Partials      339      341       +2     

Flag	Coverage Δ
e2e-ci	62.48% <ø> (+0.51%)	⬆️
e2e-full	41.77% <ø> (-16.36%)	⬇️
unit	49.30% <ø> (-0.06%)	⬇️

see 12 files with indirect coverage changes

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