message: docs: fix plugin usage typo
diff: @@ -7,20 +7,28 @@ umi plugin for [remax](https://remaxjs.org/).
  ```js
  // config in your umi project (.umirc.js or config/config.js)
  export default {
  - routes: [{
  + routes: [
  + {
  path: 'pages/a',
  - }, {
  + },
  + {
  path: 'pages/b',
  - }],
  - plugins: ['umi-plugin-remax', {
  + },
  + ],
  + plugins: [
  + [
  + 'umi-plugin-remax',
  + {
  // same with remax.config.js in remax
  cssModules: true,
  // same with app.config.js in remax
  app: {
  window: {
  defaultTitle: 'alipay mini app',
  - }
  },
  - }]
  + },
  + },
  + ],
  + ],
  };
  ```
  