This adds inlining for Babel and the Babel plugins used in next.
This is based to the PR at https://github.com/vercel/next.js/pull/18823.
The approach is to make one large bundle and then separate out the individual packages from that in order to avoid duplications.
In the first attempt the Babel bundle size was 10MB... using "resolutions" in the Yarn workspace to reduce the duplicated packages this was brought down to a 2.8MB bundle for Babel and all the used plugins which is exactly the expected file size here.
This will thus add a 2.8MB download size to the next package, but save downloading any babel dependencies separately, removing a large number of package dependencies from the overall install.
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