Fix adapter-node regression

[Conduitry]

Followup to #1754. Oops. I was writing env.js to the wrong place. It worked locally because where I wrote it to was the files directory that was copied over next build. This should be getting written directly to .svelte-kit/node/env.js after copying over everything in files in the package.

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Latest commit: 8c7b561

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

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Name	Type
@sveltejs/adapter-node	Patch

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