Use next version ref instead of 3.14

Co-authored-by: Peter Bierma <zintensitydev@gmail.com>

Author: johnslavik

Doc/library/typing.rst

@@ -2389,7 +2389,7 @@ types.
       disallowed in Python 3.15. To create a NamedTuple class with 0 fields,
       use ``class NT(NamedTuple): pass`` or ``NT = NamedTuple("NT", [])``.
 
-   .. versionchanged:: 3.14
+   .. versionchanged:: next
       Added support for calls to :func:`super` inside user-defined methods
       of ``NamedTuple`` subclasses to reuse functionality from built-in classes
       :class:`tuple` and :class:`object`.