Fix unsafe .abort() call

[Dreamsorcerer]

Possibly fixes #7252.
Definite fix for elastic/rally#1714.

.abort() is not safe to call if the transport is already closed, since Python 3.11.1:
python/cpython#98540

[codecov]

Codecov Report

Merging #7280 (6832189) into master (b2a7983) will decrease coverage by 0.01%.
The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master    #7280      +/-   ##
==========================================
- Coverage   97.31%   97.31%   -0.01%     
==========================================
  Files         107      107              
  Lines       31485    31488       +3     
  Branches     3937     3937              
==========================================
+ Hits        30640    30642       +2     
- Misses        641      642       +1     
  Partials      204      204              

Flag	Coverage Δ
CI-GHA	97.22% <80.00%> (-0.01%)	⬇️
OS-Linux	96.87% <80.00%> (-0.01%)	⬇️
OS-Windows	95.29% <80.00%> (-0.01%)	⬇️
OS-macOS	96.46% <80.00%> (-0.01%)	⬇️
Py-3.10.11	96.97% <80.00%> (-0.01%)	⬇️
Py-3.11.0	96.41% <80.00%> (-0.01%)	⬇️
Py-3.7.16	96.70% <80.00%> (-0.01%)	⬇️
Py-3.7.9	95.17% <80.00%> (-0.01%)	⬇️
Py-3.8.10	95.08% <80.00%> (-0.01%)	⬇️
Py-3.8.16	96.61% <80.00%> (-0.01%)	⬇️
Py-3.9.13	95.08% <80.00%> (-0.01%)	⬇️
Py-3.9.16	96.63% <80.00%> (-0.01%)	⬇️
Py-pypy7.3.11	94.13% <80.00%> (-0.01%)	⬇️
VM-macos	96.46% <80.00%> (-0.01%)	⬇️
VM-ubuntu	96.87% <80.00%> (-0.01%)	⬇️
VM-windows	95.29% <80.00%> (-0.01%)	⬇️

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

Impacted Files	Coverage Δ
aiohttp/connector.py	94.47% <0.00%> (-0.15%)	⬇️
tests/test_connector.py	97.88% <100.00%> (+<0.01%)	⬆️

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[bdraco]

Confirmed the leak is gone with cleanup closed set to True on my production systems

[Dreamsorcerer]

Closing in favour of python/cpython#104485
Should be released in Python 3.11.4.