Unify base tests across normal, Cloud and arm
    
    We have variant versions of several of the base tests which exist
    to account for differences in required variable settings to run
    essentially the same test in different situations. By twiddling
    the variables a little, including inventing a new variable
    defined in the flavors and substituted into the test suites so
    the same test suite can have a different START_AFTER_TEST when
    run on different flavors, I think we can unite them all and make
    this a lot simpler.
    
    Signed-off-by: Adam Williamson <awilliam@redhat.com>