list-group has double border if last element on card (v4)

Created by: filipesilva

I've added a box shadow to cards via the following css .card { box-shadow: 0 0.125em lightgrey; }

If my last element is a list-group list-group-flush then it looks like there's a second border.

Whereas if the last element on a card is something else, like an empty card-block, it looks fine.