fix issue where group stages were displayed despite tournament having none

tournaments/models/tournament.py

@@ -839,10 +839,10 @@ class Tournament(models.Model):
         return False
 
     def display_group_stages(self):
-        if self.end_date is not None:
-            return True
         if len(self.groupstage_set.all()) == 0:
             return False
+        if self.end_date is not None:
+            return True
         if self.publish_group_stages:
             return True