docs: fix links in free-threaded guide #11813

Job	Run time
resolve	4s
fmt	22s
semver-checks	27s
check-msrv	10m 55s
clippy/aarch64-apple-darwin/stable	8m 5s
python${{ matrix.python-version }}-${{ matrix.platform.python-architecture }} ${{ matrix.platform.os }} rust-${{ matrix.rust }}	0s
clippy/x86_64-unknown-linux-gnu/stable	12m 37s
careful	0s
coverage windows-latest	17m 30s
clippy/powerpc64le-unknown-linux-gnu/stable	11m 33s
coverage macos-latest	7m 54s
clippy/s390x-unknown-linux-gnu/stable	11m 43s
docsrs	0s
coverage ubuntu-latest	11m 21s
clippy/wasm32-wasi/stable	11m 7s
test-free-threaded	10m 25s
clippy/x86_64-pc-windows-msvc/stable	18m 46s
clippy/i686-pc-windows-msvc/stable	15m 8s
clippy/x86_64-unknown-linux-gnu/beta	12m 5s
valgrind	0s
check-feature-powerset ${{ matrix.rust }}	0s
emscripten	0s
test-debug	0s
test-version-limits	0s
test-cross-compilation ${{ matrix.os }} -> ${{ matrix.target }}	0s
test-cross-compilation-windows	0s
python3.12-x64 ubuntu-latest rust-nightly / build	6m 45s
python3.12-x64 macos-13 rust-stable / build	18m 45s
python3.12-arm64 macos-latest rust-stable / build	8m 43s
python3.12-x86 windows-latest rust-stable / build	13m 35s
python3.12-x64 ubuntu-latest rust-stable / build	10m 22s
python3.12-x64 windows-latest rust-stable / build	15m 26s
conclusion	1s
	3h 53m 39s

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