docs: use `$effect.pre` instead of `beforeUpdate` (#13955)

* Update 03-lifecycle-hooks.md

* Update documentation/docs/06-runtime/03-lifecycle-hooks.md

Co-authored-by: Paolo Ricciuti <ricciutipaolo@gmail.com>

---------

Co-authored-by: Paolo Ricciuti <ricciutipaolo@gmail.com>

documentation/docs/06-runtime/03-lifecycle-hooks.md

@@ -67,12 +67,13 @@ While there's no "after update" hook, you can use `tick` to ensure that the UI i
 
 ```svelte
 <script>
-	import { beforeUpdate, tick } from 'svelte';
+	import { tick } from 'svelte';
 
-	beforeUpdate(async () => {
+	$effect.pre(() => {
 		console.log('the component is about to update');
-		await tick();
+		tick().then(
-		console.log('the component just updated');
+				console.log('the component just updated');
+		);
 	});
 </script>
 ```