[3.12] GH-109190: Copyedit 3.12 What's New: Deprecations (GH-109766) (#109925)

[3.12] GH-109190: Copyedit 3.12 What's New: Deprecations (GH-109766) (#109925)

* GH-109190: Copyedit 3.12 What's New: Deprecations (GH-109766)
(cherry picked from commit 87ddfa74e2d37f6837351ed2bafc7d6d55fe2fd0)

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
* GH-109190: Copyedit 3.12 What's New: Deprecations (``os`` fix)  (#109927)

Merge the two ``os`` entries

(cherry picked from commit 0e28d0f7a1bc3776cc07e0f8b91bc43fcdbb4206)

---------

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>