[Bug Report] Sass-loader 9.0.1 prependData option removed, use additionalData instead breaks build

[avenmore]

Environment

Vuetify Version: 2.3.3
Vue Version: 2.6.11
Browsers: Firefox 78.0
OS: Windows 10

Steps to reproduce

Update sass-loader to 9.0.1 and "npm run build". Outputs a flood of errors about invalid option prependData.

Expected Behavior

Project builds.

Actual Behavior

Build fails.

Reproduction Link

Other comments

This change is listed under breaking changes for sass-loader 9.0.0.

I was able to build by hacking the following files:

...\node_modules\vuetify-loader\dev\webpack.config.js

function sassLoaderOptions (indentedSyntax = false) {
  return {
    implementation: require('sass'),
    additionalData: `@import "~@/_variables.scss"` + (indentedSyntax ? '' : ';'), //!
    sassOptions: { indentedSyntax },
  }
}

...\node_modules\vue-cli-plugin-vuetify\util\helpers.js

  } else if (sassLoaderVersion < 9) {
    if (opt.prependData) data.unshift(opt.prependData)
    opt.prependData = data.join('\n')
  } else {
    if (opt.additionalData) data.unshift(opt.additionalData)
    opt.additionalData = data.join('\n')
  }

[DRoet]

duplicate of #185