const ProjectContainer  = ({ history, routes }) => {
    const onBeforeUnload = (event) => {
        if (history.location.pathname !== '/saving-package') {
            event.returnValue = 'Changes will not be saved. This action cannot be undone';
        }
    };
    useEffect(() => {
        window.addEventListener('beforeunload', onBeforeUnload);
        return () => window.removeEventListener('beforeunload', onBeforeUnload);
    });
    return (
        // ...routes
    );
};