gh-131741: Add documentation for Windows version detection change in platform (GH-131742)

Document the behavior change between 3.11 & 3.12, where ``platform`` now correctly detects Windows 11 and Windows Server releases past Windows Server 2012.
(cherry picked from commit b9ca438)

Co-authored-by: Idan Noiman <[email protected]>
Co-authored-by: Adam Turner <[email protected]>
Co-authored-by: Hugo van Kemenade <[email protected]>
Co-authored-by: Wulian <[email protected]>

Author: 4 people

Doc/whatsnew/3.12.rst

@@ -818,6 +818,14 @@ pathlib
   :meth:`pathlib.Path.rglob` and :meth:`pathlib.PurePath.match` for matching
   the path's case sensitivity, allowing for more precise control over the matching process.
 
+platform
+--------
+
+* Add support for detecting Windows 11 and Windows Server releases past 2012.
+  Previously, lookups on Windows Server platforms newer than Windows Server 2012
+  and on Windows 11 would return ``Windows-10``.
+  (Contributed by Steve Dower in :gh:`89545`.)
+
 pdb
 ---