regression: No loader is configured for ".md" files after v5 on development with @mdx-js/rollup

[JounQin]

Describe the bug

  ✘ [ERROR] No loader is configured for ".md" files: packages/pkg/README.md

    docs/App.tsx:20:15:
      20 │       ? import(`../packages/${params.name}/README.md`)
         ╵                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


✘ [ERROR] No loader is configured for ".md" files: packages/pkg/CHANGELOG.md

    docs/App.tsx:37:15:
      37 │       ? import(`../packages/${params.name}/CHANGELOG.md`)

Reproduction

https://github.com/un-ts/mono-lib-boilerplate

Steps to reproduce

yarn
yarn dev

System Info

System:
    OS: macOS 14.1.2
    CPU: (10) arm64 Apple M1 Max
    Memory: 27.23 GB / 64.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 18.18.2 - ~/Library/Caches/fnm_multishells/76002_1701950982110/bin/node
    Yarn: 4.0.2 - ~/Library/Caches/fnm_multishells/76002_1701950982110/bin/yarn
    npm: 9.8.1 - ~/Library/Caches/fnm_multishells/76002_1701950982110/bin/npm
    bun: 1.0.15 - /opt/homebrew/bin/bun
  Browsers:
    Brave Browser: 120.1.61.100
    Chrome: 120.0.6099.62
    Safari: 17.1.2
  npmPackages:
    @vitejs/plugin-react-swc: ^3.5.0 => 3.5.0 
    vite: ^5.0.6 => 5.0.6

Used Package Manager

yarn

Logs

No response

Validations

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• Read the Contributing Guidelines.
• Read the docs.
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• The provided reproduction is a minimal reproducible example of the bug.

[XiSenao]

You can create a PR about .md, refer to the PR: #15189