fix lints for directives_ordering rule (#8382)

diff --git a/dev/bots/test.dart b/dev/bots/test.dart
index 1a2e105..99a68db 100644
--- a/dev/bots/test.dart
+++ b/dev/bots/test.dart
@@ -1,5 +1,5 @@
-import 'dart:io';
 import 'dart:async';
+import 'dart:io';
 
 import 'package:path/path.dart' as p;