[3.13] gh-149776: Skip UDP Lite tests if it's not supported (GH-149777) (#149782)

gh-149776: Skip UDP Lite tests if it's not supported (GH-149777)

Fix test_socket on Linux kernel 7.1 and newer: skip UDP Lite tests if
it's not supported.
(cherry picked from commit 3cfc249e11a132dc69624150843779aa96c72b2b)

Co-authored-by: Victor Stinner <vstinner@python.org>