[PR #10043/5255cec backport][3.11] Avoid constructing headers mulitidict twice for web.Response

[bdraco]

(cherry picked from commit 5255cec)

[codspeed-hq]

CodSpeed Performance Report

Merging #10045 will improve performances by 16.95%

_{Comparing patchback/backports/3.11/5255cecfe73c2be59e7e207449783635f4b978a2/pr-10043 (0dc5c5d) with 3.11 (65dab0e)}

Summary

⚡ 4 improvements
✅ 40 untouched benchmarks

Benchmarks breakdown

	Benchmark	3.11	patchback/backports/3.11/5255cecfe73c2be59e7e207449783635f4b978a2/pr-10043	Change
⚡	test_simple_web_response	551.8 µs	495.1 µs	+11.44%
⚡	test_web_response_with_bytes_body	643.1 µs	586.9 µs	+9.58%
⚡	test_web_response_with_headers	1,085.1 µs	927.8 µs	+16.95%
⚡	test_web_response_with_text_body	772.2 µs	705.6 µs	+9.42%

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.03%. Comparing base (65dab0e) to head (0dc5c5d).
Report is 2 commits behind head on 3.11.

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             3.11   #10045   +/-   ##
=======================================
  Coverage   98.03%   98.03%           
=======================================
  Files         122      122           
  Lines       36930    36932    +2     
  Branches     4449     4450    +1     
=======================================
+ Hits        36205    36207    +2     
  Misses        543      543           
  Partials      182      182           

Flag	Coverage Δ
CI-GHA	97.92% <100.00%> (+<0.01%)	⬆️
OS-Linux	97.63% <100.00%> (-0.01%)	⬇️
OS-Windows	94.53% <100.00%> (+<0.01%)	⬆️
OS-macOS	96.74% <100.00%> (-0.01%)	⬇️
Py-3.10.11	96.60% <100.00%> (-0.01%)	⬇️
Py-3.10.15	97.19% <100.00%> (+0.04%)	⬆️
Py-3.11.10	96.54% <100.00%> (-0.68%)	⬇️
Py-3.11.9	96.67% <100.00%> (-0.01%)	⬇️
Py-3.12.7	97.70% <100.00%> (+<0.01%)	⬆️
Py-3.13.0	97.68% <100.00%> (+<0.01%)	⬆️
Py-3.9.13	96.53% <100.00%> (-0.02%)	⬇️
Py-3.9.20	97.11% <100.00%> (+0.03%)	⬆️
Py-pypy7.3.16	96.67% <100.00%> (+<0.01%)	⬆️
VM-macos	96.74% <100.00%> (-0.01%)	⬇️
VM-ubuntu	97.63% <100.00%> (-0.01%)	⬇️
VM-windows	94.53% <100.00%> (+<0.01%)	⬆️

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

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