Thanks for FL77N for contribution of sparse-rcnn (#3634)

README_cn.md

@@ -277,7 +277,7 @@ v2.0版本已经在`04/2021`发布，全面支持动态图版本，新增支持B
 
 我们非常欢迎你可以为PaddleDetection提供代码，也十分感谢你的反馈。
 - 感谢[Mandroide](https://github.com/Mandroide)清理代码并且统一部分函数接口。
-
+- 感谢[FL77N](https://github.com/FL77N/)贡献`Sparse-RCNN`模型代码。
 
 ## 引用
 

README_en.md

@@ -283,6 +283,7 @@ PaddleDetection is released under the [Apache 2.0 license](LICENSE).
 
 Contributions are highly welcomed and we would really appreciate your feedback!!
 - Thanks [Mandroide](https://github.com/Mandroide) for cleaning the code and unifying some function interface.
+- Thanks [FL77N](https://github.com/FL77N/) for contributing the code of `Sparse-RCNN` model.
 
 ## Citation