fix validation for notification

src/Bundle/ChillMainBundle/Resources/views/Notification/show.html.twig

@@ -87,6 +87,7 @@
             </div>
         {% endif %}
 
+        {% if appendCommentForm is not null %}
         <div class="new-comment my-5">
             <h2 class="chill-blue mb-4">{{ 'Write a new comment'|trans }}</h2>
 
@@ -102,6 +103,7 @@
             {{ form_end(appendCommentForm) }}
 
         </div>
+        {% endif %}
     </div>
 
     <ul class="record_actions sticky-form-buttons">