feat(turbopack): basic sass-loader support (#4985)
### Description
WEB-654.
This is pairing PR from next.js
https://github.com/vercel/next.js/pull/49882 (not a breaking change
though) to have necessary support to run sass-loader. Mainly, it adds
near-dummy context in `webpack-loaders` as well as assigning specific
module types for the scss / sass.
I'm not entirely in favor of having internal custom module type logic in
webpack loaders setup by extension - however next.config.js itself
doesn't have enough information other than extension + loader to
determine module type. Something would like to address.
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Co-authored-by: Justin Ridgewell <justin@ridgewell.name>
