def get_release_tag(release_name, arch):
    """Determine the quay destination tag where a release image lives, based on the
    release name and arch (since we can now have multiple arches for each release name)
    - make sure it includes the arch in the tag to distinguish from any other releases of same name.

    e.g.:
    (4.2.0-0.nightly-s390x-2019-12-10-202536, s390x) remains 4.2.0-0.nightly-s390x-2019-12-10-202536
    (4.3.0-0.nightly-2019-12-07-121211, x86_64) becomes 4.3.0-0.nightly-2019-12-07-121211-x86_64
    """
    return release_name if arch in release_name else "{}-{}".format(release_name, arch)