[3.13] gh-120521: clarify except* documentation to allow tuples (GH-120523) (#120750)

(cherry picked from commit 58b3f111767148e9011ccd52660e208f0c834b2a)

Co-authored-by: Danny Yang <yangdanny97@users.noreply.github.com>
Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>