gh-108267: Fix object.__setattr__ regression in dataclasses docs (#119082)

Author: hauntsaninja

Doc/library/dataclasses.rst

@@ -615,7 +615,8 @@ methods will raise a :exc:`FrozenInstanceError` when invoked.
 
 There is a tiny performance penalty when using ``frozen=True``:
 :meth:`~object.__init__` cannot use simple assignment to initialize fields, and
-must use :meth:`!__setattr__`.
+must use :meth:`!object.__setattr__`.
+.. Make sure to not remove "object" from "object.__setattr__" in the above markup
 
 .. _dataclasses-inheritance: