VS Code: Add single file (README) to multi-root workspace

You can configure a vs-code multi-root workspace to include several folders. Eg,

{
  "folders": [
    {
      // Source code
      "name": "Product",
      "path": "vscode"
    },
    {
      // Docs and release notes
      "name": "Documentation",
      "path": "vscode-docs"
    },
    {
      // Yeoman extension generator
      "name": "Extension generator",
      "path": "vscode-generator-code"
    }
  ]
}

I would also like to include a README file from a root directory that pertains to all those folders. Is there a way to do this?