### What does this PR do?
On Linux, AbortSignal.timeout created a file descriptor for each timeout
and did not keep the event loop alive when a timer was active. This is
fixed.
### How did you verify your code works?
Fewer flaky tests
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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Claude <claude@anthropic.ai>