fix(setResponseHeaders): fix types to allow partial header names

[dargmuesli]

🔗 Linked issue

#542
resolves #614

❓ Type of change

• 📖 Documentation (updates to the documentation, readme, or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Currently, the record requires all keys to be set.
See: https://github.com/maevsi/maevsi/actions/runs/7428213670/job/20215223408

Adding Partial allows value to be undefined though. I guess the idea for undefined values would be to remove the corresponding header, but that change can be reverted of course!

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (ae91fc8) 74.65% compared to head (33a65bc) 74.67%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #607      +/-   ##
==========================================
+ Coverage   74.65%   74.67%   +0.01%     
==========================================
  Files          47       47              
  Lines        4246     4248       +2     
  Branches      574      571       -3     
==========================================
+ Hits         3170     3172       +2     
  Misses       1061     1061              
  Partials       15       15              

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[dargmuesli]

@pi0 can we have a patch release for this? 🙈

[devunt]

This issue blocks upgrading h3 to 1.10.0.