docs: update readme

Author: wxnet2013

README.md

@@ -95,7 +95,7 @@ app.dispatch({
 1. [与 Vue 集成](https://github.com/TalkingData/vue-rxloop)
 2. [与 React 集成](https://github.com/TalkingData/react-rxloop)
 
-## 插件
+## 插件
 1. [immer](https://github.com/TalkingData/rxloop-immer)
 2. [loading](https://github.com/TalkingData/rxloop-loading)
 3. [devtools](https://github.com/TalkingData/rxloop-devtools)