fix(card-group): set min height to content (#12128)

### Related Ticket(s)

[JIRA](https://jsw.ibm.com/browse/ADCMS-6840)

### Description

Adding min height to card-group component to ensure the elements have the correct height.

### Changelog

**New**
Adding min height to card-group component to ensure the elements have the correct height.

packages/styles/scss/components/card-group/_card-group.scss

@@ -77,11 +77,18 @@
         &::after {
           content: revert;
         }
+
+        &::after {
+          display: block;
+          aspect-ratio: 16 / 9;
+          content: '';
+          grid-area: 1 / 1 / -1 / -1;
+        }
       }
 
       .#{$prefix}--card__content {
         display: grid;
-        grid-row: span 10;
+        grid-area: 1 / 1 / -1 / -1;
         grid-template-rows: subgrid;
         row-gap: 0;
       }