Add Python 3.12 to the build matrix

[chris-allan]

.

[sbesson]

This PR builds wheel artifacts as expected but the Python library fails to load a runtime error due to the removal of imp in Python 3.12:

sbesson@Sebastiens-MacBook-Pro-3 artifacts % python --version
Python 3.12.1
sbesson@Sebastiens-MacBook-Pro-3 artifacts % python -mvenv venv
sbesson@Sebastiens-MacBook-Pro-3 artifacts % venv/bin/pip install zeroc_ice-3.6.5-cp312-cp312-macosx_11_0_universal2.whl 
Processing ./zeroc_ice-3.6.5-cp312-cp312-macosx_11_0_universal2.whl
Installing collected packages: zeroc-ice
Successfully installed zeroc-ice-3.6.5

[notice] A new release of pip is available: 23.2.1 -> 23.3.2
[notice] To update, run: /Users/sbesson/Downloads/artifacts/venv/bin/python -m pip install --upgrade pip
sbesson@Sebastiens-MacBook-Pro-3 artifacts % venv/bin/python -c 'import Ice'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/Users/sbesson/Downloads/artifacts/venv/lib/python3.12/site-packages/Ice.py", line 14, in <module>
    import sys, string, imp, os, threading, warnings, datetime
ModuleNotFoundError: No module named 'imp'

Minimally, this will need a Python 3.12 additional patch similar to the one proposed in glencoesoftware/zeroc-ice-py-linux-x86_64#3.

With the patch above, I have built a wheel locally on OSX (Intel) and I have used it successfully in my testing of ome/omero-py#390 for the last few weeks.

[sbesson]

Retested the three new artifacts on OSX 14.3 (Intel), by creating virtual environments, installing the wheel package as well as a development version of OMERO.py and running a few basic commands (omero login, omero import, omero delete and omero hql).

Everything worked as expected. Proposing to get that in and cut a new release of the binaries that we can start pointing at for the OMERO Python 3.12 testing