[3.10] gh-112275: Fix HEAD_LOCK deadlock in child process after fork (GH-112336) (#123687)

HEAD_LOCK is called from _PyEval_ReInitThreads->_PyThreadState_DeleteExcept before _PyRuntimeState_ReInitThreads reinit runtime->interpreters.mutex which might be locked before fork.

(cherry picked from commit 522799a05e3e820339718151ac055af6d864d463)

Co-authored-by: ChuBoning <102216855+ChuBoning@users.noreply.github.com>
Co-authored-by: Łukasz Langa <lukasz@langa.pl>