Revert "docs: add guide for on-demand import with Rspack (#16841)"

This reverts commit c2843cd.

docs/en-US/guide/quickstart.md

@@ -52,7 +52,7 @@ First you need to install `unplugin-vue-components` and `unplugin-auto-import`.
 npm install -D unplugin-vue-components unplugin-auto-import
 ```
 
-Then add the code below into your `Vite`, `Webpack` or `Rspack` config file.
+Then add the code below into your `Vite` or `Webpack` config file.
 
 ##### Vite
 
@@ -98,29 +98,6 @@ module.exports = {
 }
 ```
 
-##### Rspack
-
-Example of how to register these plugins in [Rspack](https://rspack.dev/):
-
-```js
-// rspack.config.js
-const AutoImport = require('unplugin-auto-import/rspack')
-const Components = require('unplugin-vue-components/rspack')
-const { ElementPlusResolver } = require('unplugin-vue-components/resolvers')
-
-module.exports = {
-  // ...
-  plugins: [
-    AutoImport({
-      resolvers: [ElementPlusResolver()],
-    }),
-    Components({
-      resolvers: [ElementPlusResolver()],
-    }),
-  ],
-}
-```
-
 For more bundlers ([Rollup](https://rollupjs.org/), [Vue CLI](https://cli.vuejs.org/)) and configs please reference [unplugin-vue-components](https://github.com/antfu/unplugin-vue-components#installation) and [unplugin-auto-import](https://github.com/antfu/unplugin-auto-import#install).
 
 #### Nuxt