Update cache tests to reflect new last_changed value. See #WP23448


git-svn-id: https://unit-tests.svn.wordpress.org/trunk@1206 4a5a2adb-35eb-4268-9a1b-fe04a4134342
Revert accidental slashing test updates

git-svn-id: https://unit-tests.svn.wordpress.org/trunk@1207 4a5a2adb-35eb-4268-9a1b-fe04a4134342