[3.12] Docs: for for/else clarify that return or raise also skip the else (GH-124591) (#124660)

Docs: for for/else clarify that return or raise also skip the else (GH-124591)

(cherry picked from commit 5329d1b74a86b3a22ff36f7976bfe720ee06d10d)

Co-authored-by: Ned Batchelder <ned@nedbatchelder.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>