use own api to replace jsonplaceholder.typicode.com (#7472)

Author: tanhauhau

site/content/tutorial/07-lifecycle/01-onmount/app-b/App.svelte

@@ -4,7 +4,7 @@
 	let photos = [];
 
 	onMount(async () => {
-		const res = await fetch(`https://jsonplaceholder.typicode.com/photos?_limit=20`);
+		const res = await fetch(`/tutorial/api/album`);
 		photos = await res.json();
 	});
 </script>