Defining global variable replacements in 'optimizeDeps' looks not correct.

[daief]

Describe the bug

My config file. I set a optimizeDeps and define. But the GLOBAL_VAR is replaced differently when I use GLOBAL_VAR in the module included by optimizeDeps and it looks not correct (it still be quoted after replaced).

import { defineConfig } from "vite";
import reactRefresh from "@vitejs/plugin-react-refresh";

// https://vitejs.dev/config/
export default defineConfig({
  plugins: [reactRefresh()],
  optimizeDeps: {
    include: ["@local/a"]
  },
  define: {
    GLOBAL_VAR: JSON.stringify("This is injected.")
  }
});

Reproduction

The codesandbox can reproduce the problem: https://codesandbox.io/s/vite-define-ior1b?file=/src/main.jsx

System Info

Output of npx envinfo --system --npmPackages vite,@vitejs/plugin-vue --binaries --browsers:

  System:
    OS: Linux 5.4 Debian GNU/Linux 10 (buster) 10 (buster)
    CPU: (12) x64 Intel(R) Core(TM) i7-8700 CPU @ 3.20GHz
    Memory: 7.60 GB / 62.73 GB
    Container: Yes
    Shell: 5.0.3 - /bin/bash
  Binaries:
    Node: 12.20.0 - ~/.nvm/versions/node/v12.20.0/bin/node
    Yarn: 1.22.10 - ~/.nvm/versions/node/v12.20.0/bin/yarn
    npm: 6.14.8 - ~/.nvm/versions/node/v12.20.0/bin/npm
  npmPackages:
    vite: 2.1.5 => 2.1.5

Used package manager: yarn

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