feat(typescript-estree): disallow switch statements with multiple default cases

[DMartens]

PR Checklist

• Addresses an existing open issue: fixes Enhancement: Check for switches with multiple default cases #8099
• That issue was marked as accepting prs
• Steps in Contributing were taken

Overview

Throw an error if a switch statement has multiple default cases with the same message as the TypeScript diagnostics.

[typescript-eslint]

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes are missing coverage. Please review.

Project coverage is 87.72%. Comparing base (c0da420) to head (185b04e).
Report is 111 commits behind head on main.

❗ Current head 185b04e differs from pull request most recent head 7dabbce. Consider uploading reports for the commit 7dabbce to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8411      +/-   ##
==========================================
+ Coverage   86.94%   87.72%   +0.78%     
==========================================
  Files         252      398     +146     
  Lines       12251    13830    +1579     
  Branches     3861     4068     +207     
==========================================
+ Hits        10652    12133    +1481     
- Misses       1332     1400      +68     
- Partials      267      297      +30     

Flag	Coverage Δ
unittest	87.72% <0.00%> (+0.78%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
packages/typescript-estree/src/convert.ts	28.80% <0.00%> (-0.11%)	⬇️

... and 146 files with indirect coverage changes

[JoshuaKGoldberg]

LGTM!

Will add 1 approval and leave open for a bit in case @bradzacher wants to review too, since Brad also commented on the issue.

[bradzacher]