ci: increase Windows workflow timeout on v7.x

[mcollina]

Summary

Backport the Windows CI timeout increase from #5426 to v7.x.

The v7.x workflow still gives Windows jobs a 20-minute timeout. WPT runs can exceed that under normal runner/package-install variance; for example, #5618's Windows Node.js 24 job was canceled at the 20-minute limit while WPT was still progressing.

This keeps non-Windows jobs at 20 minutes and gives Windows jobs 30 minutes.

Testing

• Workflow-only change; no local tests run.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.15%. Comparing base (3bf33e2) to head (b85f991).

Additional details and impacted files

@@            Coverage Diff             @@
##             v7.x    #5621      +/-   ##
==========================================
- Coverage   93.16%   93.15%   -0.01%     
==========================================
  Files         112      112              
  Lines       36764    36764              
==========================================
- Hits        34251    34249       -2     
- Misses       2513     2515       +2     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.