fix: skip unnecessary version.json checks if updated.current is already true

[Rich-Harris]

If we already know that there's a new deployment, updated.check() should be a no-op. Otherwise we'll request version.json when navigation fails even if we already know the answer

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from 13b2fdd:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/13b2fddeb29e04cc22ab3734b007694c75a7c5a2

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16518

[changeset-bot]

🦋 Changeset detected

Latest commit: 13b2fdd

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

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-16518-svelte.vercel.app/