[3.12] gh-110429: Fix race condition in "make regen-all" (GH-110433)#110438

vstinner merged 1 commit intopython:3.12python/cpython:3.12from

miss-islington:backport-fb6c4ed-3.12miss-islington/cpython:backport-fb6c4ed-3.12Copy head branch name to clipboard