Warn on collection membership checks that resolve to Never

[dmvinson]

Is your feature request related to a problem? Please describe.
Currently, membership checks that resolve to Never don't produce a warning, but this is almost always a mistake. An example is:

a: set[int] = {1, 2, 3}
b: set[str] = {"a", "b", "c"}

for item in a:
    if item in b:
        print(item) # type here is Never

Describe the solution you'd like
This membership check will resolve to Never (always False), it'd be nice if there was an optional configuration to make this a warning diagnostic, similar to reportUnnecessaryComparison.

[erictraut]

You probably already realized this, but pyright already has a diagnostic check for this condition: reportUnnecessaryContains. It's not enabled by default in "basic" type checking mode, but you can enable it.

[dmvinson]

Yes, thank you! Was just testing this out after finding it