Fix crash related with __getattr__ and __call__

[onlined]

Fixes #7243.

[ilevkivskyi]

Thanks for PR! I think this may be not the best to way to fix this however. An ideal fix would be to actually implement #3832. But this may be a too big task, so I think it would also make sense to essentially copy the logic from your previous PR #6655 to find_member().

Also, could you please add some tests?

[onlined]

Thanks for the review! I changed the logic as you proposed. I will add tests, but I couldn't think of some simple snippet which can call find_member with __call__. Could you give a suggestion?

[ilevkivskyi]

I think the simplest way to trigger the crash is:

from typing import Callable, Any

class C:
    def __getattr__(self, attr: str) -> C: ...

def do(cd: Callable[..., Any]) -> None:
    ...

do(C())

Using this I think you get the idea how to trigger similar crashes in constraints.py, join.py, etc. There is no need to add a test for every call site, just couple test cases will be enough.

[onlined]

Added.

[ilevkivskyi]

👍 Nice!