Support python 3.12

[BishopWolf]

For reference https://devguide.python.org/versions/

Python 3.12 is the current stable release version, therefore most systems are including it as default. Even when having a venv solves any issues, it would be good to stay updated with versions. This means support all current stable/supported versions and drop support for obsolete ones.

[tbaudier]

It's planned, maybe I will do it with that PR https://github.com/OpenGATE/opengate/tree/qt6
I will remove support for python 3.8 too

But before I wanted to try to use Py_LIMITED_API and avoiding to be dependant of python versions. But pybind is not compatible with Py_LIMITED_API pybind/pybind11#1755

[BishopWolf]

I think this is ready, so you can close this issue