chore(css_ref): remove mdn-data dependency

[caugner]

Description

Updates the css_ref macro to no longer use mdn-data.

Motivation

We want to archive mdn-data, and this removes one of two usages of mdn-data in Rari, blocking the archival.

Additional details

• This PR: https://rari-pr434.review.mdn.allizom.net/en-US/docs/Web/CSS/Reference#index
• Prod: https://developer.mozilla.org/en-US/docs/Web/CSS/Reference#index

Related issues and pull requests

Part of #369.

Extracted from #390.

[github-actions]

1f1492b was deployed to: https://rari-pr434.review.mdn.allizom.net/

[LeoMcA]

Created a very hacky inline diff view in fred to view these changes more easily, and I think it's a shame to lose the qualifier in parentheses after duplicate names:

Could we simply check for duplicate names and qualify them with the title of the parent page in parentheses?

[caugner]

Could we simply check for duplicate names and qualify them with the title of the parent page in parentheses?

Great catch. 9416d9f adds a suffix for all at-rule descriptors. As far as I can see, this was the old behavior, and there are no more duplicates.

[caugner]

@LeoMcA See https://rari-pr434.review.mdn.allizom.net/en-US/docs/Web/CSS/Reference#index for how it looks now.

[LeoMcA]

code lgtm, but has content approved?

[dipikabh]

Spot checked the list for quite a few alphabets. It's looking good!