/**
     * Returns {@link Artifact} instance where to relocate to, or {@code null}.
     *
     * @param session The session, never {@code null}.
     * @param result The artifact descriptor result, never {@code null}.
     * @param model The artifact model, never {@code null}.
     * @return The {@link Artifact} to relocate to, or {@code null} if no relocation wanted.
     */