KDE: Allow AArch64 live media to fail for now
    
    Unfortunately, there are serious issues with Lorax on AArch64 that
    impair its reliability. Until Fedora KDE artifacts can move off
    Lorax, we cannot make non-x86_64 live images release blocking.
    
    Signed-off-by: Neal Gompa <ngompa@fedoraproject.org>