Update README.md

Author: xdd666t

README.md

@@ -4,7 +4,7 @@ Language:  English | [中文](https://juejin.cn/post/7026150456673959943)
 
 Migrate doc：[3.x migrate 4.0](https://github.com/fluttercandies/flutter_smart_dialog/blob/master/docs/3.x%20migrate%204.0.md) | [3.x 迁移 4.0](https://juejin.cn/post/7093867453012246565)
 
-Flutter 2：Please use `flutter_smart_dialog: 4.0.1`
+Flutter 2：Please use `flutter_smart_dialog: 4.0.2`
 
 Flutter 3：Please use the latest version