Correct use of asyncio.Lock to process a single control message at a time #3471

Job	Run time
Test Lint	1m 11s
test_docs	1m 48s
Make SDist	1m 14s
link_check	3m 46s
build (ubuntu-latest, 3.13)	4m 45s
Test Prereleases	1m 54s
test_without_debugpy (ubuntu-latest, 3.9)	1m 56s
check_release	1m 53s
build (ubuntu-latest, 3.12)	5m 30s
build (ubuntu-latest, 3.9)	4m 5s
build (ubuntu-latest, 3.10)	4m 41s
build (ubuntu-latest, pypy-3.10)	3m 30s
build (macos-latest, 3.10)	4m 27s
build (macos-latest, 3.13)	4m 45s
build (windows-latest, 3.11)	6m 18s
build (ubuntu-latest, 3.11)	4m 22s
build (windows-latest, 3.9)	5m 7s
build (macos-latest, pypy-3.10)	3m 59s
build (windows-latest, 3.13)	6m 21s
build (macos-latest, 3.9)	4m 27s
build (macos-latest, 3.11)	4m 29s
build (windows-latest, pypy-3.10)	6m 8s
build (windows-latest, 3.12)	6m 31s
build (macos-latest, 3.12)	5m 27s
build (windows-latest, 3.10)	6m 42s
Test Minimum Versions	3m 50s
Install from SDist and Test	2m 21s
coverage	0s
	1h 51m 27s

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