feat(core): Parent Ticket validation added to ticket serializer

ref: #554 closes #517

app/core/serializers/ticket.py

@@ -310,6 +310,28 @@ class TicketModelSerializer(
                 data['status'] = int(Ticket.TicketStatus.All.NEW)
 
 
+        if(
+            data['parent_ticket']
+            and (
+                self._context['view'].action == 'partial_update'
+                or self._context['view'].action == 'update'
+            )
+        ):
+
+            if not data['parent_ticket'].circular_dependency_check(
+                ticket = self.instance,
+                parent = data['parent_ticket']
+            ):
+
+                raise centurion_exception.ValidationError(
+                    detail = {
+                        'parent_ticket': 'Adding this ticket will create a circular dependency'
+                    },
+                    code = 'no_parent_circular_dependency',
+                )
+
+
+
         self.validate_field_organization()
 
         self.validate_field_milestone()