[3.14] gh-146004: propagate all -X options to multiprocessing child processes (GH-146005) (#146552)

gh-146004: propagate all -X options to multiprocessing child processes (GH-146005)

Propagate all -X command line options to multiprocessing spawned child Python processes.
(cherry picked from commit 1efe441de7c448852b9ba51fb0db4d355a7157a8)

Co-authored-by: Gregory P. Smith <68491+gpshead@users.noreply.github.com>