[3.13] pythongh-124984: Enhance ssl thread safety (pythonGH-124993)

Make SSL objects thread safe in Free Theaded build by
using critical sections.

(cherry picked from commit 4c53b25)

Co-authored-by: Peter Bierma <[email protected]>
Co-authored-by: Bénédikt Tran <[email protected]>

Author: ZeroIntensity