When setting `WP_TESTS_FORCE_KNOWN_BUGS` to `true`, it is preferable that some forced tests are still skipped when they call classes or functions that do not exist, producing fatal errors.

Fixes #26248.



git-svn-id: https://develop.svn.wordpress.org/trunk@26370 602fd350-edb4-49c9-b593-d223f7449a82