Use primary button in Ground Nav (#2145)

Author: tylersticka

.changeset/brave-moles-decide.md

@@ -0,0 +1,5 @@
+---
+'@cloudfour/patterns': minor
+---
+
+Use primary button style for Ground Nav action so it will appear more prominent visually

src/components/ground-nav/ground-nav.twig

@@ -20,6 +20,7 @@
           </h2>
           <p class="c-ground-nav__action-title">
             {% include '@cloudfour/components/button/button.twig' with {
+              class: 'c-button--primary',
               href: link,
               label: title,
               content_start_icon: icon ?? 'link'