Repository: create-react-app
Issue: Leading slah in url() being removed in scss files
Labels: needs triage,issue: bug report

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### Describe the bug

I have a path set in a scss file to a resource I need referenced off the root of the domain. Since v4, the css-loader by default tries to resolve css references to src folder. I've tried using react-app-rewired to set the `{ url: false }` option for css-loader, and it no longer [complains about the missing reference](https://github.com/facebook/create-react-app/issues/9937), but for some reason the leading slash still gets stripped.

`url('/path/to/file') -> url('path/to/file')`

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Yes, npm version: 6.14.17

### Environment

current version of create-react-app: 5.0.1
  running from /Users/323782896/.npm/_npx/61421/lib/node_modules/create-react-app

  System:
    OS: macOS 12.4
    CPU: (8) x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz
  Binaries:
    Node: 14.17.4 - /usr/local/bin/node
    Yarn: Not Found
    npm: 6.14.17 - /usr/local/bin/npm
  Browsers:
    Chrome: 103.0.5060.114
    Edge: Not Found
    Firefox: 101.0
    Safari: 15.5
  npmPackages:
    react: ^17.0.2 => 17.0.2
    react-dom: ^17.0.2 => 17.0.2
    react-scripts: ^4.0.3 => 4.0.3
  npmGlobalPackages:
    create-react-app: Not Found
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### Steps to reproduce

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1. Set css-loader `url` option to `false` with react-app-rewired for use of unresolved references
```
// config-overrides.js

const { override, adjustStyleLoaders } = require('customize-cra');

module.exports = override(
  adjustStyleLoaders(({ use: [miniExtract, css, postcss, resolveUrl, sass] }) => {
    css.options = { ...css.options, url: false };
  })
);
```
2. `react-app-rewired start` or `react-app-rewired build`

### Expected behavior

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`url('/path/to/file')`

### Actual behavior

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`url('path/to/file')`

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