no-empty-source performance optimization

[gucong3000]

Describe the issue. Is it a bug or a feature request (new rule, new option, etc.)?

A bug when lint CSS in HTML about no-empty-source

Which rule, if any, is this issue related to?

no-empty-source

What CSS is needed to reproduce this issue?

html file without css.
https://github.com/vuejs-templates/webpack/blob/master/template/index.html

What stylelint configuration is needed to reproduce this issue?

module.exports = {
  rules: {
    "no-empty-source": true,
  }
}

Which version of stylelint are you using?

stylelint@8.0.0

How are you running stylelint: CLI, PostCSS plugin, Node API?

CLI with stylelint "**/*.{vue,html,css,sss,less,scss,sass}" --custom-syntax postcss-html

Does your issue relate to non-standard syntax (e.g. SCSS, nesting, etc.)?

Yes, it's related to HTML.

What did you expect to happen?

No warnings to be flagged.

What actually happened (e.g. what warnings or errors you are getting)?

The following warnings were flagged:

index.html
 35:1  ×  Unexpected empty source   no-empty-source