Add object.__new__

Not entirely sure about the right signature, though.

builtins/3/builtins.pyi

@@ -30,6 +30,7 @@ class object:
     __class__ = ...  # type: type
 
     def __init__(self) -> None: ...
+    def __new__(cls) -> Any: ...
     def __eq__(self, o: object) -> bool: ...
     def __ne__(self, o: object) -> bool: ...
     def __str__(self) -> str: ...