wireguard: Show status of default route in server information page

Tests:

- Create a server connection with default route setting 'on'. See that the
server status page reflects the value correctly. Repeat for 'off'.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/modules/wireguard/templates/wireguard_show_server.html

@@ -40,6 +40,17 @@
               <th>{% trans "IP address of this machine:" %}</th>
               <td>{{ server.ip_address }}</td>
             </tr>
+            <tr class="server-default-route">
+              <th>
+                {% trans "All outgoing traffic is sent using this connection:" %}
+              </th>
+              <td>{% if server.default_route %}
+                    {% trans "Yes" %}
+                  {% else %}
+                    {% trans "No" %}
+                  {% endif %}
+              </td>
+            </tr>
           </tbody>
         </table>
       </div>