docs: update URLs for new svelte.dev site

[benmccann]

this was tedious 😝

[changeset-bot]

🦋 Changeset detected

Latest commit: 970701c

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

This PR includes changesets to release 12 packages

Name	Type
@sveltejs/adapter-cloudflare-workers	Patch
@sveltejs/adapter-cloudflare	Patch
@sveltejs/adapter-netlify	Patch
@sveltejs/adapter-static	Patch
@sveltejs/adapter-vercel	Patch
@sveltejs/adapter-auto	Patch
@sveltejs/adapter-node	Patch
@sveltejs/enhanced-img	Patch
svelte-migrate	Patch
@sveltejs/package	Patch
@sveltejs/amp	Patch
@sveltejs/kit	Patch

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