feat(virtualization): Add Q-in-Q SVLAN to VMinterface template (#19345)

Author: pheus

netbox/templates/virtualization/vminterface.html

@@ -55,6 +55,12 @@ <h2 class="card-header">{% trans "Interface" %}</h2>
           <th scope="row">{% trans "802.1Q Mode" %}</th>
           <td>{{ object.get_mode_display|placeholder }}</td>
         </tr>
+        {% if object.mode == 'q-in-q' %}
+          <tr>
+              <th scope="row">{% trans "Q-in-Q SVLAN" %}</th>
+              <td>{{ object.qinq_svlan|linkify|placeholder }}</td>
+          </tr>
+        {% endif %}
         <tr>
           <th scope="row">{% trans "Tunnel" %}</th>
           <td>{{ object.tunnel_termination.tunnel|linkify|placeholder }}</td>