WIP add 3.12 tests

[Almenon]

I also dropped support for 3.7, which is really end-of-life now that 3.8 is EOL

[Almenon]

python/arepl_python_evaluator.py:235: in exec_input
    asyncio.set_event_loop(asyncio.new_event_loop())
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/asyncio/events.py:758: in new_event_loop
    return get_event_loop_policy().new_event_loop()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/asyncio/events.py:722: in get_event_loop_policy
    _init_event_loop_policy()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/asyncio/events.py:715: in _init_event_loop_policy
    from . import DefaultEventLoopPolicy

NameError: name 'unix_events' is not defined
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/asyncio/init.py:45: NameError

What a strange error. I don't get this on my Windows machine. I re-ran but got same error. Not worth looking into because I'm removing asyncio.set_event_loop(asyncio.new_event_loop()) in #193

[Almenon]

moved these changes to #193