[3.14] gh-143553: Add support for parametrized resources in regrtests (GH-143554) (GH-143555)

For example, "-u xpickle=2.7" will run test_xpickle only against Python 2.7.
(cherry picked from commit c07e5ec0a9e5843fc39dec6aa94172faf6354858)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>