update Contents function

src/pages/blog/[...slug].astro

@@ -24,9 +24,9 @@ interface Props {
 }
 
 const { post } = Astro.props;
-const { Content } = await post.render();
+const { Content, headings } = await post.render();
 ---
 
-<PostLayout post={post}>
+<PostLayout post={post} headings={headings}>
   <Content components={mdxComponents} />
 </PostLayout>