Add bpo-42914 to What's New (GH-25124)

BPO-42914 was not added to the What's New in GH-24864. This includes it in the "Improved Modules" section.

Automerge-Triggered-By: GH:gpshead
(cherry picked from commit 4846ea9)

Co-authored-by: Wm. Keith van der Meulen <[email protected]>

Author: miss-islington

Doc/whatsnew/3.10.rst

@@ -1137,6 +1137,9 @@ identification from `freedesktop.org os-release
 pprint
 ------
 
+:func:`pprint.pprint` now accepts a new ``underscore_numbers`` keyword argument.
+(Contributed by sblondon in :issue:`42914`.)
+
 :mod:`pprint` can now pretty-print :class:`dataclasses.dataclass` instances.
 (Contributed by Lewis Gaul in :issue:`43080`.)
 

Misc/ACKS

@@ -1821,6 +1821,7 @@ Andi Vajda
 Case Van Horsen
 John Mark Vandenberg
 Kyle VanderBeek
+Wm. Keith van der Meulen
 Eric N. Vander Weele
 Andrew Vant
 Atul Varma