Update to new C API for Python 3.13

[limburgher]

src_c/math.c: In function ‘com_init’:
src_c/math.c:4425:10: error: implicit declaration of function ‘_PyArg_NoKeywords’ [-Werror=implicit-function-declaration]
4425 | if (!_PyArg_NoKeywords("ClassObjectMethod", kwds))
| ^~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors

https://bugzilla.redhat.com/show_bug.cgi