[docs] fix typo in 02-template-syntax.md (#7593)

Tiny typo.

Author: a-alexander

site/content/docs/02-template-syntax.md

@@ -1666,7 +1666,7 @@ If `this` is the name of a void tag (e.g., `br`) and `<svelte:element>` has chil
 
 The `<svelte:window>` element allows you to add event listeners to the `window` object without worrying about removing them when the component is destroyed, or checking for the existence of `window` when server-side rendering.
 
-Unlike `<svelte:self>`, this element may only appear the top level of your component and must never be inside a block or element.
+Unlike `<svelte:self>`, this element may only appear at the top level of your component and must never be inside a block or element.
 
 ```sv
 <script>