fix(megamenu): add padding between category desc and link (#5118)

### Related Ticket(s)

Web component: Mega Menu MVP - accommodations for HC + AI updates - Visual QA (Firefox, Chrome) #5089

### Description

Add padding between the category description and first link.

### Changelog

**Changed**

- set 8px bottom padding to category copy

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packages/styles/scss/components/masthead/_masthead-megamenu.scss

@@ -171,7 +171,7 @@
     ::slotted(#{$dds-prefix}-megamenu-category-group-copy) {
       color: $text-01;
       margin-top: rem(-6px);
-      padding: 0 $spacing-05 1px $spacing-05;
+      padding: 0 $spacing-05 $spacing-03 $spacing-05;
     }
   }