[3.13] gh-127001: Fix PATHEXT issues in shutil.which() on Windows (GH… #133464

Job	Run time
Change detection / Compute changed files	9s
Check if generated files are up to date	2m 3s
Check if the ABI has changed	1m 25s
Check if Autoconf files are up to date	27s
Docs	0s
Address sanitizer	9m 7s
Ubuntu SSL tests with OpenSSL (ubuntu-22.04, 3.0.15)	2m 14s
Ubuntu SSL tests with OpenSSL (ubuntu-22.04, 3.1.7)	2m 18s
Hypothesis tests on Ubuntu	4m 31s
Ubuntu SSL tests with OpenSSL (ubuntu-22.04, 3.2.3)	2m 16s
Windows MSI${{ '' }}	0s
Ubuntu SSL tests with OpenSSL (ubuntu-22.04, 3.3.2)	2m 41s
CIFuzz	0s
Thread sanitizer / Thread sanitizer	3m 14s
Thread sanitizer (free-threading) / Thread sanitizer	7m 4s
WASI / build and test	10m 19s
macOS (free-threading) / build and test (ghcr.io/cirruslabs/macos-runner:sonoma)	8m 9s
macOS / build and test (ghcr.io/cirruslabs/macos-runner:sonoma)	5m 55s
macOS / build and test (macos-13)	9m 13s
Ubuntu / build and test (ubuntu-22.04)	6m 29s
Ubuntu (free-threading) / build and test (ubuntu-22.04)	9m 16s
Windows / build (arm64)	1m 54s
Windows (free-threading) / build (arm64)	14s
Windows / build and test (Win32)	1s
Windows / build and test (x64)	1s
Windows (free-threading) / build and test (Win32)	1s
Windows (free-threading) / build and test (x64)	1s
All required checks pass	4s
	1h 29m 6s

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