fix watching unassigned task in the dashboard

app/modules/home/duties/duty.jade

@@ -1,8 +1,13 @@
 a(href="{{ ::vm.duty.get('url') }}", title="{{ ::duty.get('subject') }}")
-    img.avatar(
+
+    img.avatar(ng-if="::vm.duty.get('assigned_to_extra_info')"
         ng-src="{{ ::vm.duty.get('assigned_to_extra_info').get('photo') }}"
         title="{{ ::vm.duty.get('assigned_to_extra_info').get('full_name_display') }}")
 
+    img.avatar(ng-if="::!vm.duty.get('assigned_to_extra_info')"
+        src="/images/unnamed.png"
+        title="{{'ACTIVITY.VALUES.UNASSIGNED' | translate}}")
+
     div.duty-data
         div
             span.duty-type {{ ::vm.getDutyType() }}