btlogging setLevel does nothing

```py
from bittensor.utils.btlogging import logging

print(logging.get_level())  # prints 30
logging.setLevel(20)
print(logging.get_level())  # prints 30
```

I would expect this to set the logging level to 20, but it does not.

If this is expected, it should be documented (`LoggingMachine` subclasses `logging.Logger`, and thus has that method.)