bootstrap 4 theme - card dropdown is not opening in menu after Add to cart

 For bootstrap4 theme, I had to change/add this to open dropdown with card info 

```
$('li.dropdown.vstore-storecart').addClass('show');
 $('li.dropdown.vstore-storecart #vstore-cart-dropdown').addClass('show');
```
BT3 used open class, BT4 show on 2 places. 