pythongh-101880: add link to object.__hash__() in hash() builtin docu…

…mentation (pythonGH-101883)

(cherry picked from commit ec7180b)

Co-authored-by: Owain Davies <116417456+OTheDev@users.noreply.github.com>

Doc/library/functions.rst

@@ -793,7 +793,7 @@ are always available.  They are listed here in alphabetical order.
 
       For objects with custom :meth:`__hash__` methods, note that :func:`hash`
       truncates the return value based on the bit width of the host machine.
-      See :meth:`__hash__` for details.
+      See :meth:`__hash__ <object.__hash__>` for details.
 
 .. function:: help()
               help(request)