fix: svelte:component spread props change not picked up

[hackape]

fix #9003, amend #8946 (comment)

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[changeset-bot]

🦋 Changeset detected

Latest commit: 6a8a315

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

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svelte	Patch

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[dummdidumm]

Thank you! Could you add a test so we don't regress in the future?

[hackape]

test added

[dummdidumm]

Thank you!