next.js

5df64654 - Turbopack: cleanup StyleSheetLike (#85718)

Turbopack: cleanup StyleSheetLike (#85718) This abstraction was a leftover from when we had a swc_css and a lightningcss backend. Also inspired by https://github.com/vercel/next.js/pull/85524 as there was another constant-false `PartialEq` impl.