fix(card): push the footer to the bottom of the card consistently (#1…

…2137)

### Related Ticket(s)

[ADCMS-7121](https://jsw.ibm.com/browse/ADCMS-7121)
[ADCMS-7158](https://jsw.ibm.com/browse/ADCMS-7158)

### Description

Under certain conditions, the footer of a card, especially within a group, might not stick to the end of the card as intended. This fixes it so that the card footer is always at the end of the card.

### Changelog

**Changed**

- Force the footer of cards to be at the end, corrects an issue with Content Group Cards

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

@@ -117,6 +117,12 @@
       }
     }
 
+    .#{$prefix}--card {
+      display: flex;
+      flex-direction: column;
+      justify-content: space-between;
+    }
+
     .#{$prefix}--card__wrapper {
       display: flex;
       flex: 1;