Incorrect type when descriptors are at different levels in the class hierarchy

When `__get__` and `__set__` are at different levels in the class hierarchy, they do not seem to be behaving properly. Example: ```py from typing import assert_type, cast, Any class AttributeGet[ T ]: def __get__( self, instance: Any, owner: Any = None ) -> T: return cast( Any, None ) class Attribute[ T, U ]( AttributeGet[ T ] ): def __set__( self, instance: Any, object: T | U ) -> None: pass class StrInt( Attribute[ int, str] ): pass class MyContainer: si: StrInt c = MyContainer() c.si = "2" assert_type( c.si, int ) # ERROR HERE ``` Playground [link](https://pyright-play.net/?code=GYJw9gtgBALgngBwJYDsDmUkQWEMoCGAzkQKZ4D68CpANFAMbEz0CCKcAsAFA8MA2xIlFYwYIJACMArjFIBxUjADaUACpQAugC4eUfQBNSwKBQpolZgBRQy-YPVREYBFA1LaRHemADuKck92OCgAXigAOTAAqABKKABaAD51XW59DKgQJWkQFEZmG2D6KJjYnj5BEhExCRk5VTV6AFUtItqpWQUlRq04tIyjEzMyGGtbUntHFGdXdyDvKDBJACtSBhhPDQAfKFb45Mjojz1MqAQhCu4BISgAZXEASRQYdvFOhswX%2BmcQTX7TvoLiQrjdqgBZOAAYWiLlQgUBRCQngeIGeMFBYSgkJhLwI8JAVnK1wAdEisQAiABMFJ4QnIY2opBsDDJSGm%2BGJQA)