[8.18] Stop using event_loop fixture (#2969)

[pquentin]

Backport

This will backport the following commits from main to 8.18:

• Stop using event_loop fixture (#2969)

Questions ?

Please refer to the Backport tool documentation

[github-actions]

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[github-actions]

The backport to 8.17 failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-8.17 8.17
# Navigate to the new working tree
cd .worktrees/backport-8.17
# Create a new branch
git switch --create backport-2973-to-8.17
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 e6e4d184c5e856b0874509a85e4644f0e2b6f912
# Push it to GitHub
git push --set-upstream origin backport-2973-to-8.17
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-8.17

Then, create a pull request where the base branch is 8.17 and the compare/head branch is backport-2973-to-8.17.