fix: apply correct styles to audio descriptions track menu items

[david-hm-morgan]

Description

Fix #8769 for mismatched track kind should be plural descriptions according to definition of AudioTrackKind
#8769

Specific Changes proposed

Pluralisation

Requirements Checklist

• Feature implemented / Bug fixed
• If necessary, more likely in a feature request than a bug fix
  • Change has been verified in an actual browser (Chrome, Firefox, IE)
  • Unit Tests updated or fixed
  • Docs/guides updated
  • Example created (starter template on JSBin)
  • Has no DOM changes which impact accessiblilty or trigger warnings (e.g. Chrome issues tab)
  • Has no changes to JSDoc which cause npm run docs:api to error
• Reviewed by Two Core Contributors

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 83.01%. Comparing base (2b3ffd4) to head (e8e85f7).

Files	Patch %	Lines
...-bar/audio-track-controls/audio-track-menu-item.js	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8770   +/-   ##
=======================================
  Coverage   83.01%   83.01%           
=======================================
  Files         119      119           
  Lines        7993     7993           
  Branches     1923     1923           
=======================================
  Hits         6635     6635           
  Misses       1358     1358           

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[mister-ben]

Thanks!

[amtins]

LGTM 👍🏽

[welcome]

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