bpo-24596: Decref module in PyRun_SimpleFileExFlags() on SystemExit (GH-7918) (GH-8070)

PyErr_Print() will not return when the exception is a SystemExit, so
decref the __main__ module object in that case.
(cherry picked from commit d8cba5d16f1333fd625726fc72e66afbd45b8d00)

Co-authored-by: Zackery Spytz <zspytz@gmail.com>
3 files changed