fix: check that component wasn't instantiated

[dummdidumm]

fixes #10454

Svelte 4 version of #10458

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🦋 Changeset detected

Latest commit: 750292a

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

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[benmccann]

Svelte 4 version of #10463

I think you meant to refer to a different PR?

[dummdidumm]

Thanks, updated reference