Remove rust-cpython support from documentation #3932

Job	Run time
Check ${{ matrix.platform.target }}	0s
Generate Matrix	9s
Test Alpine Linux	0s
Test Auditwheel	0s
Test Cross Compile	0s
Test Docker	0s
Test Bootstrap (ubuntu-latest)	2m 57s
Test downstream - ${{ matrix.downstream.repository }}	0s
Test Emscripten	0s
Test Bootstrap (macos-14)	2m 42s
Test Bootstrap (windows-latest)	5m 11s
Test MSRV	2m 11s
Test Pyston	0s
Test (ubuntu-latest, 3.12)	28m 19s
Test (ubuntu-latest, pypy3.10)	11m 15s
Test (macos-14, 3.12)	9m 16s
Test (windows-latest, 3.12)	21m 5s
Test (windows-latest, pypy3.10)	24m 45s
conclusion	1s
	1h 47m 51s

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