widen contextlib._SupportsClose and _SupportsAclose (#5655)

stdlib/contextlib.pyi

@@ -39,7 +39,7 @@ if sys.version_info >= (3, 7):
     def asynccontextmanager(func: Callable[_P, AsyncIterator[_T]]) -> Callable[_P, AsyncContextManager[_T]]: ...  # type: ignore
 
 class _SupportsClose(Protocol):
-    def close(self) -> None: ...
+    def close(self) -> object: ...
 
 _SupportsCloseT = TypeVar("_SupportsCloseT", bound=_SupportsClose)
 
@@ -48,7 +48,7 @@ class closing(ContextManager[_SupportsCloseT]):
 
 if sys.version_info >= (3, 10):
     class _SupportsAclose(Protocol):
-        async def aclose(self) -> None: ...
+        async def aclose(self) -> object: ...
     _SupportsAcloseT = TypeVar("_SupportsAcloseT", bound=_SupportsAclose)
     class aclosing(AsyncContextManager[_SupportsAcloseT]):
         def __init__(self, thing: _SupportsAcloseT) -> None: ...