[3.13] gh-118934: Make PyEval_GetLocals return borrowed reference (GH-119769) (#121869)

gh-118934: Make PyEval_GetLocals return borrowed reference (GH-119769)
(cherry picked from commit e65cb4c6f01a687f451ad9db1600525e1c5832c4)

Co-authored-by: Tian Gao <gaogaotiantian@hotmail.com>
Co-authored-by: Alyssa Coghlan <ncoghlan@gmail.com>