Revert "Bump cmarkgfm from 0.4.2 to 0.5.0" (#8877)
Revert "Bump cmarkgfm from 0.4.2 to 0.5.0" (#8877)

This reverts commit b71e1aa01515c3162be63eec0dcddd07d650c459.
pypa/warehouse,pypa/warehouse,pypa/warehouse,pypa/warehouse