fix: treat each blocks with async dependencies as uncontrolled

[Rich-Harris]

Oddly enough I can't seem to produce a failing test around this, but the following code...

<script lang="ts">
	import Dummy from './Dummy.svelte';

	const array = await [1, 2];
</script>

<article>
	{#each await array}
		<div>
			<Dummy />
		</div>
	{/each}
</article>

...will fail to hydrate, because of the is_controlled optimisation being incorrectly applied.

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@17077

[changeset-bot]

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