Fix vanilla-extract noExternal error

[williamlark]

Our setNoExternalPlugin would silently leave packages external that use a different version of @vanilla-extract/css. Apps shouldn't have multiple versions, but not externalizing packages based on that should still not happen.

For example, previously:

app ──► braid-design-system ──► @vanilla-extract/css 1.21   (recorded first)
 └────► some-chart-lib ───────► @vanilla-extract/css 1.20   (throws, left external)

Here some-chart-lib is left external, so Node loads it from node_modules at runtime without sku's Vanilla Extract processing and with its own module instances. That can fail at import, or render different markup or class names on the server than on the client, which shows up as hydration errors.

I was able to test this in an app by creating a locally linked package that has a pinned dep to an older @vanilla-extract/css. Importing it into the app fails with "Styles were unable to be assigned to file" errors, and it resolved when updating to a snapshot release of this brach.

[changeset-bot]

🦋 Changeset detected

Latest commit: d9f7be6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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sku	Patch

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