remove rollup-plugin-styles from the list

[just-boris]

Awesome Contribution Checklist:

• I have read, and re-read the Contributing Guidelines
• I have searched to ensure the suggested item doesn't exist on this list
• This PR contains only one item

Please Provide a Link A Repository for Your Addition Removal

https://github.com/Anidetrix/rollup-plugin-styles

Please Describe Your Addition Removal

This package is unmaintained and only supports rollup 2.x. There were attempts to contribute new version support, but no response: Anidetrix/rollup-plugin-styles#225

At this point it would be better not to confuse people by suggesting an outdated package

[just-boris]

If anybody is interested, I got some luck with this package: https://github.com/jleeson/rollup-plugin-import-css

It is not a full equivalent, but it supports CSS and Rollup 4.x. I can submit this addition as a follow up

[egnor]

This seems sane enough; I'm inclined to merge it @shellscape ?

It looks like the main descendant, https://github.com/plumelo/rollup-plugin-styler, is already present. The maintainer of https://github.com/jleeson/rollup-plugin-import-css says they're working on a test so it can be included as well.