fix updating sphinx_delta on new uploads to existing group

classes/torrents.class.php

@@ -504,7 +504,7 @@ public static function update_hash($GroupID) {
             INNER JOIN torrents_tags tt ON (tt.GroupID = g.ID)
             INNER JOIN tags t2 ON (t2.ID = tt.TagID)
             WHERE g.ID = ?
-            GROUP BY g.ID
+            GROUP BY t.ID
             ", $VoteScore, $ArtistName, $GroupID
         );