fedora.conf: force new ostree commits for AH/Silverblue
    
    This will ensure that the OSTrees get generated on each compose
    so that the media created will match the version numbers of the
    OSTree inside.
    
    The caveat is that there can be empty commits that do happen.
    
    Signed-off-by: Dusty Mabe <dusty@dustymabe.com>