[feature-request] Special case E721 (use isinstance instead of type comparison) for type(None)

[smackesey]

Comparison to type(None) occasionally comes up in our codebase:

if context.dagster_type.typing_type == type(None):
    return None

This raises a ruff/flake8 error: E721 Do not compare types, use isinstance().

IMO this rule should not apply for comparisons to type(None), since the "correct" form implied by the rule looks very odd:

if isinstance(None, context.dagster_type.typing_type):
    return None

I think this weirdness is unique to type(None).