Invalid options object. PostCSS Loader has been initialized using an options object

问题描述
Invalid options object. PostCSS Loader has been initialized using an options object that does not match the API schema.

options has an unknown property ‘plugins’. These properties are valid:
object { postcssOptions?, execute?, sourceMap?, implementation? }
这个问题是我们在使用postcss-pxtorem运行项目的时候的报错，其实并不难，好多人就把报错放到百度上搜，怎么都解决不了，其实我们仔细读一下大概意思就是：

postcss应该是个对象，但是这个对象没有plugins,只有{ postcssOptions?, execute?, sourceMap?, implementation?}这四个属性，修改后用postcssOptions包住plugins就好了，下面是修改后的配置，其实好多报错我们认证读一下就能找到解决方法

// vue.config.js
module.exports = {
  css: {
    loaderOptions: {
      postcss: {
        postcssOptions: {
          plugins: [
            require("postcss-pxtorem")({ rootValue: 16, propList: ["*"] }),
          ],
        },
      },
    },
  },
};