Fix all variants to delete-after so we dont keep accumulating things.
    
    In 57985b08 nightly was updated, but not all the variants were updated
    in the second sync. The first sync runs with --exclude repodata, then
    the second one includes that and also does a --delete-after, but we only
    updated the first one. This should clean up old artifacts.
    
    Signed-off-by: Kevin Fenzi <kevin@scrye.com>