[PR #11198/b151d3fc backport][3.12] Fix auto-created TCPConnector not using session's event loop

[patchback]

This is a backport of PR #11198 as merged into 3.13 (b151d3f).

What do these changes do?

This PR restores the loop parameter that was accidentally removed from the TCPConnector instantiation in ClientSession when PR #11095 was merged. When a ClientSession is created without an explicit connector, it auto-creates a TCPConnector. This connector should use the same event loop as the session to maintain consistency.

Are there changes in behavior for the user?

No behavior changes for users. This is a bug fix that restores the previous correct behavior where the auto-created TCPConnector uses the same event loop as the ClientSession.

Is it a substantial burden for the maintainers to support this?

No, this is a simple one-line fix that restores a parameter that was accidentally removed. The pattern of passing the loop parameter to connectors is well-established throughout the codebase and is already tested. This change adds minimal maintenance burden and includes a test to prevent regression.

Related issue number

Fixes #11147

Checklist

• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
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  • if you don't have an issue number, change it to the pull request
    number after creating the PR

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      improper undesired behavior that got corrected to match
      pre-agreed expectations.
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    Fixed issue with non-ascii contents in doctest text files
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[codspeed-hq]

CodSpeed Performance Report

Merging #11199 will not alter performance

_{Comparing patchback/backports/3.12/b151d3fce4d96aba7209bcaba0ec0690c793920e/pr-11198 (a5993ac) with 3.12 (bd374b1)}

Summary

✅ 59 untouched benchmarks

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.28%. Comparing base (bd374b1) to head (a5993ac).
⚠️ Report is 60 commits behind head on 3.12.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             3.12   #11199      +/-   ##
==========================================
- Coverage   98.31%   98.28%   -0.03%     
==========================================
  Files         132      132              
  Lines       43499    43506       +7     
  Branches     2380     2380              
==========================================
- Hits        42765    42760       -5     
- Misses        558      567       +9     
- Partials      176      179       +3     

Flag	Coverage Δ
CI-GHA	98.18% <100.00%> (-0.03%)	⬇️
OS-Linux	97.88% <100.00%> (-0.08%)	⬇️
OS-Windows	95.66% <100.00%> (+<0.01%)	⬆️
OS-macOS	97.20% <100.00%> (+<0.01%)	⬆️
Py-3.10.11	96.84% <100.00%> (+<0.01%)	⬆️
Py-3.10.18	96.77% <100.00%> (-0.57%)	⬇️
Py-3.11.13	97.52% <100.00%> (-0.01%)	⬇️
Py-3.11.9	95.24% <100.00%> (+<0.01%)	⬆️
Py-3.12.10	97.13% <100.00%> (+1.79%)	⬆️
Py-3.12.11	97.06% <100.00%> (-0.57%)	⬇️
Py-3.13.3	97.29% <100.00%> (-0.57%)	⬇️
Py-3.9.13	96.74% <100.00%> (+<0.01%)	⬆️
Py-3.9.23	?
Py-pypy7.3.16	?
VM-macos	97.20% <100.00%> (+<0.01%)	⬆️
VM-ubuntu	97.88% <100.00%> (-0.08%)	⬇️
VM-windows	95.66% <100.00%> (+<0.01%)	⬆️

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