fix: Fix Escape handling in menus

[mister-ben]

Description

Fixes that Escape being pressed isn't closing menus due to incorrect event.key name.
Fixes #8915

Specific Changes proposed

Replaces Esc with Escape.

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

[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 2 lines in your changes missing coverage. Please review.

Project coverage is 83.43%. Comparing base (ecef37c) to head (43f431a).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/js/menu/menu-button.js	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8916      +/-   ##
==========================================
+ Coverage   83.25%   83.43%   +0.18%     
==========================================
  Files         120      120              
  Lines        8097     8097              
  Branches     1944     1944              
==========================================
+ Hits         6741     6756      +15     
+ Misses       1356     1341      -15     

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