小图标素材地址：https://www.iconfont.cn/

添加的方法：

//webpack.prod.conf.js中添加如下代码

const path = require('path') ;
       .....
new HtmlWebpackPlugin({
    filename: config.build.index,
    template: 'index.html',
    favicon: path.resolve('./favicon.ico'),
    inject: true,
}),

//在webpack.prod.dev.js中添加如下代码：
const path = require('path');
      .....
new HtmlWebpackPlugin({
    filename: 'index.html',
    template: 'index.html',
    favicon: path.resolve('./favicon.ico'),
    inject: true,
}),

//在index.html中的title下面添加下面代码
<link rel="shortcut icon" type="image/x-icon" href="./favicon.ico" rel="external nofollow" />