docs: bump last_modified on runtime landing page

Forgotten in #3172 when the page was substantially rewritten.

Author: bartlomieju

runtime/index.md

@@ -1,5 +1,5 @@
 ---
-last_modified: 2025-10-10
+last_modified: 2026-05-28
 title: "Welcome to Deno"
 description: "Learn the basics of Deno, a secure JavaScript, TypeScript, and WebAssembly runtime."
 pagination_next: /runtime/getting_started/first_project/