[C API] Use new PyDict_GetItemRef() C API

Bug report

Checklist

• I am confident this is a bug in CPython, not a bug in a third-party project
• I have searched the CPython issue tracker,
  and am confident this bug has not been reported before

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Output from running 'python -VV' on the command line:

No response

A clear and concise description of the bug:

Calls to PyDict_GetItem() should be replaced with PyDict_GetItemRef().

PyDict_GetItemWithError() may also be replaced with PyDict_GetItemRef().

Linked PRs

• gh-108308: Replace PyDict_GetItem() with PyDict_GetItemRef() #108309
• gh-108308: config_dict_get() uses PyDict_GetItemRef() #108371
• gh-108308: Replace _PyDict_GetItemStringWithError() #108372
• gh-108308: Use PyDict_GetItemRef() in moduleobject.c #108381
• gh-108308: Remove _PyDict_GetItemStringWithError() function #108426