更换 readme 中的链接

```md
[![](https://img.shields.io/badge/%24-donate-green.svg)](https://gitissue.com/issues/5aa5176fd9e7a0126b9885e0)


<p align="center">
  <img src="https://gitissue.com/public/GitIssue1.jpg?love=gitissue" alt="GitIssue: Github Issue 博客平台">
</p>
```