Memory leak with static iterator types

Python does not finalizes iterators of some types at exit leading to memory leak.

Reproducer:

```py
a = type(iter(tuple[int]))
print(a.mro())
```

Leak:
```console
[<class 'generic_alias_iterator'>, <class 'object'>]
[119 refs, 46 blocks]
```

See also https://github.com/python/cpython/issues/90575