fix(typing): make Response headers covariant

[tonnico]

Issue number: #3743

Summary

Changes

Change typing for headers in Response constructor.

User experience

Able to use covariant of dicts, e.g.

headers_with_str = {"str": "str"}
Response(200, headers=headers_with_str)

headers_with_list = {"str": "str", "list": ["1"]}
Response(200, headers=headers_with_list)

Checklist

If your change doesn't seem to apply, please leave them unchecked.

• Meet tenets criteria
• I have performed a self-review of this change
• Changes have been tested
• Changes are documented
• PR title follows conventional commit semantics

Is this a breaking change?

RFC issue number:

Checklist:

• Migration process documented
• Implement warnings (if it can live side by side)

Acknowledgment

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[boring-cyborg]

Thanks a lot for your first contribution! Please check out our contributing guidelines and don't hesitate to ask whatever you need.
In the meantime, check out the #python channel on our Powertools for AWS Lambda Discord: Invite link

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.38%. Comparing base (e14e768) to head (cc7ff50).
⚠️ Report is 2520 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3745   +/-   ##
========================================
  Coverage    96.38%   96.38%           
========================================
  Files          214      214           
  Lines        10030    10030           
  Branches      1846     1846           
========================================
  Hits          9667     9667           
  Misses         259      259           
  Partials       104      104           

☔ View full report in Codecov by Sentry.
📢 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.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[heitorlessa]

thank you @wurstnase for this quick fix w/ Mapping generic. Everyone appreciates it :)

[boring-cyborg]

Awesome work, congrats on your first merged pull request and thank you for helping improve everyone's experience!