docs: update readme

Author: janryWang

README.md

@@ -2,7 +2,7 @@ English | [简体中文](./README.zh-cn.md)
 
 <p align="center">
 <img src="https://img.alicdn.com/tfs/TB1fHhZu4D1gK0jSZFyXXciOVXa-2500-1200.png">
-<img src="https://img.shields.io/npm/dt/@formily/antd"/>
+<img src="https://img.shields.io/npm/dt/@formily/core"/>
 <img src="https://img.shields.io/npm/dm/@formily/core"/>
 <a href="https://www.npmjs.com/package/@formily/core"><img src="https://img.shields.io/npm/v/@formily/core.svg"></a>
 <a href="https://codecov.io/gh/alibaba/formily">

README.zh-cn.md

@@ -2,7 +2,7 @@
 
 <p align="center">
 <img src="https://img.alicdn.com/tfs/TB1fHhZu4D1gK0jSZFyXXciOVXa-2500-1200.png">
-<img src="https://img.shields.io/npm/dt/@formily/antd"/>
+<img src="https://img.shields.io/npm/dt/@formily/core"/>
 <img src="https://img.shields.io/npm/dm/@formily/core"/>
 <a href="https://www.npmjs.com/package/@formily/core"><img src="https://img.shields.io/npm/v/@formily/core.svg"></a>
 <a href="https://codecov.io/gh/alibaba/formily">