MWPW-159032: Accessibility requirements for ratings comment field

[joaquinrivero]

• Adds a floating label as accessibility requirements for comments field

Resolves: MWPW-159032

Test URLs:

• Before: https://main--dc--adobecom.hlx.page/acrobat/online/test/sign-pdf-projectunity?martech=off
• After: https://mwpw-159032--dc--adobecom.hlx.page/acrobat/online/test/sign-pdf-projectunity?milolibs=MWPW-159032-ratings--milo--joaquinrivero&martech=off

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 95.96%. Comparing base (5ddeb73) to head (84eef60).
Report is 5 commits behind head on stage.

Additional details and impacted files

@@            Coverage Diff             @@
##            stage    #2949      +/-   ##
==========================================
- Coverage   96.29%   95.96%   -0.33%     
==========================================
  Files         240      175      -65     
  Lines       54739    46859    -7880     
==========================================
- Hits        52709    44970    -7739     
+ Misses       2030     1889     -141     

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[github-actions]

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