Less 中使用 http的资源地址，路径会解析错误

[minjs1cn]

Describe the bug

the url in less, may be resolve error.

Reproduction

Example

System Info

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

  System:
    OS: macOS Mojave 10.14.6
    CPU: (4) x64 Intel(R) Core(TM) i5-7267U CPU @ 3.10GHz
    Memory: 986.89 MB / 8.00 GB
    Shell: 3.2.57 - /bin/bash
  Binaries:
    Node: 14.16.0 - /usr/local/bin/node
    Yarn: 1.22.4 - /usr/local/bin/yarn
    npm: 6.14.11 - /usr/local/bin/npm
  Browsers:
    Chrome: 91.0.4472.77
    Safari: 14.1
  npmPackages:
    vite: ^2.3.5 => 2.3.5 

Used package manager:

Logs

GET http://localhost:3001/minixs/https://a.com/test.png 404 (Not Found)

---

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[bluwy]

Still reproducible in Vite 2.9.0-beta.0. Note the issue is in src/style/index.less where the Less file is transform into

const __vite__css = "body {\n  background-image: url('../minixs/https://a.com/test.png');\n}\n"

in dev mode. Notice that the url should not have a prefix of ../minixs/.