For this one we actually lose a test result. However, this is kind of to
be expected since we no longer have the "precise" MRO that the points-to
analysis computes.

Honestly, I'm on the fence about even keeping this query at all. It
seems like it might be superfluous in a world with good Python type
checking.

It's not possible for a class to actually inherit from itself, so if
this happens, something has gone wrong with our analysis. We therefore
explicitly exclude these results so they don't result in false
positives.