Automatically add contained width class if not a full width section

src/patterns/03-layouts/layout/_layout.twig

@@ -24,6 +24,9 @@
   {% if pattern_lab %}
     class="{{ classes }}"
   {% else %}
+    {% if not attributes.hasClass('uw-full-width') %}
+      {% set classes = classes|merge(['uw-contained-width']) %}
+    {% endif %}
     {{ attributes.addClass(classes) }}
   {% endif %}
 >