Rely on .content class for link hover padding in .hero components

The one place where we know it is used so far has the .content class already.

Removing it here prevents it from mucking up the secondary menu level when it
is placed within the hero-classed title section.

agaric/sass/agaric/_component.hero.scss

@@ -111,8 +111,6 @@
     &:hover {
       color: $blue-light;
       background-color: $white;
-      padding: $link-hover-padding;
-      margin: -$link-hover-padding;
     }
   }
 }