For some context:
https://vercel.slack.com/archives/CGU8HUTUH/p1662124179102509
Adds `@next/font` package.
`scripts/update-google-fonts.js` generates functions and metadata for
all available google fonts. The metadata is used in `loader.ts` to
validate font options (from #40221). It then fetches the CSS from google
fonts, downloads the font files and emits them as static assets.
The actual integration with `packages/next` and integration tests
depends on #40221, will follow up with new PR.
Co-authored-by: JJ Kasper <jj@jjsweb.site>
