docs: minor updates to pyenv installs #9767

Job	Run time
fmt	21s
check-msrv	9m 47s
semver-checks	2m 53s
python${{ matrix.python-version }}-${{ matrix.platform.python-architecture }} ${{ matrix.platform.os }} rust-${{ matrix.rust }}	0s
careful	0s
coverage windows-latest	5s
clippy/aarch64-apple-darwin/stable	7m 12s
coverage macos-14	7s
docsrs	0s
clippy/x86_64-unknown-linux-gnu/stable	12m 0s
coverage ubuntu-latest	14m 22s
clippy/powerpc64le-unknown-linux-gnu/stable	11m 26s
valgrind	0s
clippy/s390x-unknown-linux-gnu/stable	11m 54s
check-feature-powerset	0s
clippy/wasm32-wasi/stable	11m 8s
clippy/x86_64-pc-windows-msvc/stable	18m 15s
clippy/i686-pc-windows-msvc/stable	16m 2s
emscripten	0s
clippy/x86_64-unknown-linux-gnu/beta	13m 20s
test-debug	0s
test-version-limits	0s
test-cross-compilation ${{ matrix.os }} -> ${{ matrix.target }}	0s
test-cross-compilation-windows	0s
python3.12-x64 macos-13 rust-stable / build	10m 19s
python3.12-x64 windows-latest rust-stable / build	13m 6s
python3.12-x64 ubuntu-latest rust-stable / build	8m 10s
python3.12-x86 windows-latest rust-stable / build	13m 9s
python3.12-arm64 macos-14 rust-stable / build	4m 59s
python3.12-x64 ubuntu-latest rust-nightly / build	7m 2s
conclusion	1s
	3h 5m 38s

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