Fix keepalive race condition

[Dreamsorcerer]

Fixes #9138.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.31%. Comparing base (0da00a1) to head (43bffc8).
Report is 2 commits behind head on master.

✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #9140   +/-   ##
=======================================
  Coverage   98.30%   98.31%           
=======================================
  Files         107      107           
  Lines       34433    34461   +28     
  Branches     4085     4089    +4     
=======================================
+ Hits        33850    33879   +29     
  Misses        411      411           
+ Partials      172      171    -1     

Flag	Coverage Δ
CI-GHA	98.20% <100.00%> (+<0.01%)	⬆️
OS-Linux	97.87% <100.00%> (+<0.01%)	⬆️
OS-Windows	96.28% <100.00%> (+<0.01%)	⬆️
OS-macOS	97.54% <100.00%> (+<0.01%)	⬆️
Py-3.10.11	97.64% <100.00%> (+<0.01%)	⬆️
Py-3.10.14	97.57% <100.00%> (+<0.01%)	⬆️
Py-3.11.9	97.80% <100.00%> (+<0.01%)	⬆️
Py-3.12.5	97.92% <100.00%> (+<0.01%)	⬆️
Py-3.12.6	?
Py-3.9.13	97.53% <100.00%> (+<0.01%)	⬆️
Py-3.9.19	97.47% <100.00%> (+<0.01%)	⬆️
Py-pypy7.3.16	97.08% <100.00%> (+<0.01%)	⬆️
VM-macos	97.54% <100.00%> (+<0.01%)	⬆️
VM-ubuntu	97.87% <100.00%> (+<0.01%)	⬆️
VM-windows	96.28% <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.

[patchback]

Backport to 3.10: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 37e3aa4 on top of patchback/backports/3.10/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140

Backporting merged PR #9140 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https:/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.10/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140 upstream/3.10

4. Now, cherry-pick PR Fix keepalive race condition #9140 contents into that branch:

   $ git cherry-pick -x 37e3aa4639193c6423562a4a4dfbf3310772b7a6

   If it'll yell at you with something like fatal: Commit 37e3aa4639193c6423562a4a4dfbf3310772b7a6 is a merge but no -m option was given., add -m 1 as follows instead:

   $ git cherry-pick -m1 -x 37e3aa4639193c6423562a4a4dfbf3310772b7a6

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Fix keepalive race condition #9140 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.10/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https:/sanitizers/patchback-github-app.

[patchback]

Backport to 3.11: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply 37e3aa4 on top of patchback/backports/3.11/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140

Backporting merged PR #9140 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https:/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.11/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140 upstream/3.11

4. Now, cherry-pick PR Fix keepalive race condition #9140 contents into that branch:

   $ git cherry-pick -x 37e3aa4639193c6423562a4a4dfbf3310772b7a6

   If it'll yell at you with something like fatal: Commit 37e3aa4639193c6423562a4a4dfbf3310772b7a6 is a merge but no -m option was given., add -m 1 as follows instead:

   $ git cherry-pick -m1 -x 37e3aa4639193c6423562a4a4dfbf3310772b7a6

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Fix keepalive race condition #9140 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.11/37e3aa4639193c6423562a4a4dfbf3310772b7a6/pr-9140

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https:/sanitizers/patchback-github-app.