GH-101100: Resolve reference warnings in library/stdtypes.rst (#138420)

Doc/library/stdtypes.rst

@@ -4755,11 +4755,12 @@ other sequence-like behavior.
 
 There are currently two built-in set types, :class:`set` and :class:`frozenset`.
 The :class:`set` type is mutable --- the contents can be changed using methods
-like :meth:`~set.add` and :meth:`~set.remove`.  Since it is mutable, it has no
-hash value and cannot be used as either a dictionary key or as an element of
-another set.  The :class:`frozenset` type is immutable and :term:`hashable` ---
-its contents cannot be altered after it is created; it can therefore be used as
-a dictionary key or as an element of another set.
+like :meth:`add <frozenset.add>` and :meth:`remove <frozenset.add>`.
+Since it is mutable, it has no hash value and cannot be used as
+either a dictionary key or as an element of another set.
+The :class:`frozenset` type is immutable and :term:`hashable` ---
+its contents cannot be altered after it is created;
+it can therefore be used as a dictionary key or as an element of another set.
 
 Non-empty sets (not frozensets) can be created by placing a comma-separated list
 of elements within braces, for example: ``{'jack', 'sjoerd'}``, in addition to the

Doc/tools/.nitignore

@@ -29,7 +29,6 @@ Doc/library/pyexpat.rst
 Doc/library/select.rst
 Doc/library/socket.rst
 Doc/library/ssl.rst
-Doc/library/stdtypes.rst
 Doc/library/termios.rst
 Doc/library/test.rst
 Doc/library/tkinter.rst