ui: Adds definition-table class to RTT values table (#8286)

We changed our default definition list layout in
https://github.com/hashicorp/consul/pull/8117.

We replaced the default with a definition-table class but missed one
place where the old default was previously used.

This adds the definition-table class in RTT where it used to use the
default.

ui-v2/app/templates/dc/nodes/show/rtt.hbs

@@ -1,5 +1,6 @@
 <div id="round-trip-time" class="tab-section">
   <div role="tabpanel">
+    <div class="definition-table">
       <dl>
           <dt>
               Minimum
@@ -20,6 +21,7 @@
               {{format-number tomography.max maximumFractionDigits=2}}ms
           </dd>
       </dl>
+    </div>
     <TomographyGraph @tomography={{tomography}} />
   </div>
 </div>