添加Vercer一键部署按钮

[zcns]

添加Vercer部署按钮
已修改PR中使用 Vercel 这个部署按钮，会创建一个新项目而不是 fork 本项目，这个会导致 git 无法正确检查更新的错误

[netlify[bot]]

👷 Deploy request for mmplayer pending review.

Visit the deploys page to approve it

Name	Link
🔨 Latest commit	fa8d30ff66b36e667def99d62fa322daa20a66bb

[vercel[bot]]

Someone is attempting to deploy a commit to a Personal Account owned by @maomao1996 on Vercel.

@maomao1996 first needs to authorize it.

[maomao1996]

这个快捷按钮只能 clone 项目