Doesn't work in python 3.10

Description of Bug

Python API crashes on python 3.10, since it uses timezone.UTC, which is an alias that was only introduced in 3.11.

Steps To Reproduce

Steps to reproduce the behavior:

1. Try running it on 3.10

Expected behavior

Runs correctly

Actual Behaviour

    from simvue.config.user import SimvueConfiguration
../../../Library/Caches/pypoetry/virtualenvs/simvue-moose-SyxDCI6N-py3.10/lib/python3.10/site-packages/simvue/config/user.py:39: in <module>
    from simvue.eco.config import EcoConfig
../../../Library/Caches/pypoetry/virtualenvs/simvue-moose-SyxDCI6N-py3.10/lib/python3.10/site-packages/simvue/eco/__init__.py:11: in <module>
    from .emissions_monitor import CO2Monitor as CO2Monitor
../../../Library/Caches/pypoetry/virtualenvs/simvue-moose-SyxDCI6N-py3.10/lib/python3.10/site-packages/simvue/eco/emissions_monitor.py:41: in <module>
    class CO2Monitor(pydantic.BaseModel):
../../../Library/Caches/pypoetry/virtualenvs/simvue-moose-SyxDCI6N-py3.10/lib/python3.10/site-packages/simvue/eco/emissions_monitor.py:82: in CO2Monitor
    _last_local_write = pydantic.PrivateAttr(datetime.datetime.now(tz=datetime.UTC))
E   AttributeError: module 'datetime' has no attribute 'UTC'

Inizia da simvue/eco/emissions_monitor.py, in corrispondenza della definizione di CO2Monitor mostrata nel traceback, e riproduci l'errore di importazione con Python 3.10. Controlla i test esistenti del progetto o la configurazione dei test per verificare quali versioni di Python sono supportate. Il lavoro è completato quando la Python API viene importata ed eseguita correttamente con Python 3.10 senza compromettere le versioni supportate più recenti.