Vertical button group variations example has an un-rounded top

Created by: rohit2sharma95

On the button group page, the last example under the vertical variations has an un-rounded top.

Comment by @mdo and Codepen.

This is because the current selector to remove the rounded corner is https://github.com/twbs/bootstrap/blob/49934b2bba514582c92bd423f94ddbf890bc3a66/scss/_button-group.scss#L137 And the label in the button group is not the first child (First child is the input in real)