chore: speed up regex

[dummdidumm]

This regex can take longer than expected in certain situations, making it more explicit and adding "not a whitespace" to the set speeds it up
Related sveltejs/language-tools#2363

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[changeset-bot]

🦋 Changeset detected

Latest commit: 4584ee5

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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svelte	Patch

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