Remove gl-new-card from group advanced settings

What does this MR do and why?

Removes gl-new-card from GlCard that we want to keep as GlCard and not CrudComponent (see Migration: GlCard (gl-new-card variant) to Crud (#476988) for more details)

• This means the styling is reverted back to gray header, white content

Project and organizations --> Remove new-card classes from project and organi... (!161637 - merged)

Screenshots or screen recordings

Before	After

How to set up and validate locally

Group > Settings > General > Advanced

Links

• ✂️ UX Paper Cuts 17.3 → Dark mode - Design Support (#452231 - closed)
• Migration: GlCard (gl-new-card variant) to Crud (#476988)