Fix updated logic for all posts page

src/pages/posts.astro

@@ -10,8 +10,8 @@ import { SITE_TITLE, SITE_DESCRIPTION } from "../config";
 // Use Astro.glob() to fetch all posts, and then sort them by date.
 const posts = (await Astro.glob("../posts/*.md")).sort(
 	(a, b) =>
-		new Date(b.frontmatter.added).valueOf() -
-		new Date(a.frontmatter.added).valueOf()
+		new Date(b.frontmatter.updated || b.frontmatter.added).valueOf() -
+		new Date(a.frontmatter.updated || a.frontmatter.added).valueOf()
 );
 ---