title: build with multi page don't work with vite 2.6 and vue 3.2
body: <p>I made a simple multipage app with vue 3.2 and vite 2.6</p>
  <pre><code>|-src
  |---main.js
  |-package.json
  |-vite.config.js
  |-index.html
  |-validation_password.html
  </code></pre>
  <p>But when I want to build it: vite build only the index page (and not the validation-password).
  I tried to modify my vite.config.js with rollup Options like <a href="https://vitejs.dev/guide/build.html#multi-page-app" rel="nofollow noreferrer">here</a> :</p>
  <pre><code>const { resolve } = require('path')
  
  module.exports = defineConfig({
    build: {
      rollupOptions: {
        input: {
          main: resolve(__dirname, 'index.html'),
          valpass: resolve(__dirname, 'validation_password.html')
        }
      }
    }
  })
  </code></pre>
  <p>the build failed. and i have this error in my terminal:</p>
  <pre><code>[rollup-plugin-dynamic-import-variables] Unexpected token (1:0)
  file: C:/wamp64/www/IMB/VueJS/vuejs/src/PassVal.vue:1:0
  error during build:
  SyntaxError: Unexpected token (1:0)
      at Parser.pp$5.raise (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:19495:13)
      at Parser.pp.unexpected (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:16820:8)
      at Parser.pp$4.parseExprAtom (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18870:10)
      at Parser.pp$4.parseExprSubscripts (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18662:19)
      at Parser.pp$4.parseMaybeUnary (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18628:17)
      at Parser.pp$4.parseExprOps (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18561:19)
      at Parser.pp$4.parseMaybeConditional (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18544:19)
      at Parser.pp$4.parseMaybeAssign (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18512:19)
      at Parser.pp$4.parseExpression (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:18476:19)
      at Parser.pp$1.parseStatement (C:\wamp64\www\IMB\VueJS\vuejs\node_modules\rollup\dist\shared\rollup.js:17010:45)
  npm ERR! code ELIFECYCLE
  npm ERR! errno 1
  npm ERR! components-portail-math@0.0.1 build: `vite build`
  npm ERR! Exit status 1
  npm ERR!
  npm ERR! Failed at the components-portail-math@0.0.1 build script.
  npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
  
  npm ERR! A complete log of this run can be found in:
  npm ERR!     C:\Users\willb\AppData\Roaming\npm-cache\_logs\2021-10-07T14_34_53_913Z-debug.log
  </code></pre>
  <p>My PassVal.vue file break no worries locally.
  I don't understand. I'm following the doc.</p>