stdlib: Improve a bunch of __(a)exit__ methods (#7571)

stdlib/asyncio/events.pyi

@@ -123,7 +123,7 @@ class AbstractServer:
     def close(self) -> None: ...
     if sys.version_info >= (3, 7):
         async def __aenter__(self: Self) -> Self: ...
-        async def __aexit__(self, *exc: Any) -> None: ...
+        async def __aexit__(self, *exc: object) -> None: ...
         @abstractmethod
         def get_loop(self) -> AbstractEventLoop: ...
         @abstractmethod