CI Gating:  Disable fedora-ci.koji-build.tier0.functional
    
    Disable fedora-ci.koji-build.tier0.functional because of
    https://gitlab.com/testing-farm/general/-/issues/37
    
    With this update, fedora-ci.koji-build.tier0.functional will
    still be executed, but it's test result will not be taken into
    account for gating purposes.
    
    Once the aforementioned CI Infrastructure issue is resolved,
    we can roll this update back.