gh-101100: Fix sphinx warnings in `library/asyncio-subprocess.rst` #144650

Job	Run time
Change detection / Create context from changed files	9s
Check if Autoconf files are up to date	0s
Check if generated files are up to date	0s
Windows ${{ ((fromJSON(matrix.free-threading) && '(free-threading)') \|\| '') }}	0s
macOS ${{ ((fromJSON(matrix.free-threading) && '(free-threading)') \|\| '') }}	0s
Ubuntu ${{ ((fromJSON(matrix.free-threading) && '(free-threading)') \|\| '') }} ${{ ((fromJSON(matrix.bolt) && '(bolt)') \|\| '') }}	0s
Ubuntu SSL tests with OpenSSL	0s
WASI	0s
Windows MSI${{ '' }}	0s
Thread sanitizer ${{ ((fromJSON(matrix.free-threading) && '(free-threading)') \|\| '') }}	0s
Address sanitizer	0s
CIFuzz	0s
Cross build Linux	0s
Hypothesis tests on Ubuntu	0s
Docs / Docs	1m 58s
Docs / Doctest	4m 48s
All required checks pass	3s
	6m 58s

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