Issue with `test_main_log` and `test_log_system_probe_unconfigured` test

The error message:

    def test_log_system_probe_unconfigured():
        # if probe loggers aren't configured to run, then we shouldn't even call
        # _probe_system()
        logger_names = [
            'openfe.utils.system_probe.log',
            'openfe.utils.system_probe.log.gpu',
            'openfe.utils.system_probe.log.hostname',
        ]
        # check that initial conditions are as expected
        for logger_name in logger_names:
            logger = logging.getLogger(logger_name)
>           assert not logger.isEnabledFor(logging.DEBUG)
E           assert not True
E            +  where True = <bound method Logger.isEnabledFor of <Logger openfe.utils.system_probe.log (DEBUG)>>(10)
E            +    where <bound method Logger.isEnabledFor of <Logger openfe.utils.system_probe.log (DEBUG)>> = <Logger openfe.utils.system_probe.log (DEBUG)>.isEnabledFor
E            +    and   10 = logging.DEBUG

To reproduce:

$ pytest --pyargs openfecli --pyargs openfe -v -k "test_log_system_probe_unconfigured or test_main_log"
tests/test_cli.py::test_main_log[True] PASSED                            [ 33%]
tests/test_cli.py::test_main_log[False] PASSED                           [ 66%]
tests/utils/test_system_probe.py::test_log_system_probe_unconfigured FAILED [100%]

If you swap the order we run the tests in, the error goes away.

$ pytest --pyargs openfe --pyargs openfecli -v -k "test_log_system_probe_unconfigured or test_main_log"
tests/utils/test_system_probe.py::test_log_system_probe_unconfigured PASSED [ 33%]
tests/test_cli.py::test_main_log[True] PASSED                            [ 66%]
tests/test_cli.py::test_main_log[False] PASSED                           [100%]

I discovered this while fixing #610

Start by running the pytest command shown for tests/test_cli.py::test_main_log and tests/utils/test_system_probe.py::test_log_system_probe_unconfigured in both orders. Read those tests and the logging setup they exercise, then identify why logger state persists between tests. Done means both tests pass consistently regardless of collection order.