Cleanup test_faulthandler sanitizer skip logic. (GH-11381)


Also skip the same tests when using the undefined behavior sanitizer
as they much with the output.

Updates a regex in another test to use multi-line mode so that the ubsan
buildbot should pass again rather than also adding a skip to that one.
(cherry picked from commit 30e023256aa1b00d4c783553752fc6f2cc0b9b27)

Co-authored-by: Gregory P. Smith <greg@krypto.org>
1 file changed