tests: Replace STI tests with upstream FMF tests
    
    Upstream now includes FMF metadata and the setup/run scripts to run the
    nondestructive verify tests in a provided testbed. These are now
    constantly being verified through packit.
    
    Drop the code duplication and just add some minimal FMF metadata to
    discover the tests.
    
    This currently has to hardcode the version number. This eventually must
    become more flexible in FMF (https://github.com/psss/tmt/issues/585),
    but until then we can update this in the cockpituous release scripts.