Fixed a html error "Element ul is not closed" in logger.html.twig

src/Symfony/Bundle/WebProfilerBundle/Resources/views/Collector/logger.html.twig

@@ -113,7 +113,9 @@
 
             <li>Called from {{ call.file is defined and call.line is defined ? call.file|format_file(call.line, from) : from|raw }}</li>
 
-            {{ index == log.context.stack|length - 1 ? '</ul>' : '' }}
+            {% if index == log.context.stack|length - 1 %}
+                </ul>
+            {% endif %}
         {% endfor %}
     {% else %}
         {{ log.priorityName }} - {{ log.message }}