Merge branch 'fix/645' into 'develop'

Update moderation_event-detail.html

Closes #645

See merge request hub/hub!1086

src/backoffice/templates/backoffice/moderation_event-detail.html

@@ -94,8 +94,8 @@
             <dt class="col-sm-3">{% trans "Event__public_speakers" %}:</dt>
             <dd class="col-sm-9">
               {% for speaker in object.public_speakers %}
-                - <a href="{% url "backoffice:moderation-user-detail" pk=speaker.participant.id %}"
-    title="{{ speaker.participant.username }}">{{ speaker.participant.get_display_name }}</a>
+                - <a href="{% url "backoffice:moderation-user-detail" pk=speaker.id %}"
+    title="{{ speaker.username }}">{{ speaker.get_display_name }}</a>
                 <br>
               {% empty %}-/-
               {% endfor %}