Fix order of comments (#2835)

Author: Morlinest

models/issue_comment.go

@@ -611,6 +611,7 @@ func findComments(e Engine, opts FindCommentsOptions) ([]*Comment, error) {
 	}
 	return comments, sess.
 		Asc("comment.created_unix").
+		Asc("comment.id").
 		Find(&comments)
 }