Update `clinic.rst` from CPython#1167

Merged

erlend-aasland merged 2 commits intopython:mainfrom

AA-Turner:clinic-updates

Oct 1, 2023

Commits on Aug 19, 2023

python/cpython#107704: Argument Clinic: add support for deprecating keyword use of parameters (python/cpython#107984)

committed

Commits on Aug 30, 2023

python/cpython#108494: Argument Clinic: Document how to generate code that uses the limited C API (python/cpython#108584)

committed