Fix textarea tutorial example code

The textarea tutorial example code was missing a `>` at the end.

site/content/tutorial/06-bindings/05-textarea-inputs/text.md

@@ -5,5 +5,5 @@ title: Textarea inputs
 The `<textarea>` element behaves similarly to a text input in Svelte — use `bind:value`:
 
 ```html
-<textarea bind:value={markdown}></textarea
-```
+<textarea bind:value={markdown}></textarea>
+```