Fix console toolbar render when bookmark feature is disabled and sql debug is enabled

It made the display weird because a empty div was added

Signed-off-by: William Desportes <williamdes@wdes.fr>

templates/console/toolbar.twig

@@ -1,6 +1,6 @@
 <div class="toolbar {{ parent_div_classes }}">
     {% for content in content_array %}
-        {% if content is defined %}
+        {% if content is defined and content is not null %}
         <div class="{{ content[0] }}">
             {{ content['image'] is defined ? content['image']|raw }}
             <span>{{ content[1] }}</span>