gh-101100: Fix sphinx warnings in `library/enum.rst` (#114696)

Co-authored-by: Ethan Furman <ethan@stoneleaf.us>

Doc/library/enum.rst

@@ -286,6 +286,19 @@ Data Types
          appropriate value will be chosen for you.  See :class:`auto` for the
          details.
 
+   .. attribute:: Enum._name_
+
+      Name of the member.
+
+   .. attribute:: Enum._value_
+
+      Value of the member, can be set in :meth:`~object.__new__`.
+
+   .. attribute:: Enum._order_
+
+      No longer used, kept for backward compatibility.
+      (class attribute, removed during class creation).
+
    .. attribute:: Enum._ignore_
 
       ``_ignore_`` is only used during creation and is removed from the
@@ -823,8 +836,8 @@ Supported ``_sunder_`` names
 - :attr:`~Enum._ignore_` -- a list of names, either as a :class:`list` or a
   :class:`str`, that will not be transformed into members, and will be removed
   from the final class
-- :attr:`~Enum._order_` -- used in Python 2/3 code to ensure member order is
-  consistent (class attribute, removed during class creation)
+- :attr:`~Enum._order_` -- no longer used, kept for backward
+  compatibility (class attribute, removed during class creation)
 - :meth:`~Enum._generate_next_value_` -- used to get an appropriate value for
   an enum member; may be overridden
 

Doc/tools/.nitignore

@@ -31,7 +31,6 @@ Doc/library/email.compat32-message.rst
 Doc/library/email.errors.rst
 Doc/library/email.parser.rst
 Doc/library/email.policy.rst
-Doc/library/enum.rst
 Doc/library/exceptions.rst
 Doc/library/faulthandler.rst
 Doc/library/fcntl.rst