Fix: bind:scroll resets scroll state

[Black1358]

This is simply fix to the issue #11468; When initial state for $state() === undefined || null bind:scroll don't set window.scroll to 0;

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closed #11468

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 3d5ad649cd379ee2dc8328054ab4ad295f60a481

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[Rich-Harris]

thank you!