[Examples] fix remark link in blog-starter's README (#11177)

examples/blog-starter/README.md

@@ -4,7 +4,7 @@ This example showcases Next.js's [Static Generation](https://nextjs.org/docs/bas
 
 The blog posts are stored in `/_posts` as markdown files with front matter support. Adding a new markdown file in there will create a new blog post.
 
-To create the blog posts we use [`remark`](https://github.com/gnab/remark) and [`remark-html`](https://github.com/remarkjs/remark-html) to convert the markdown files into an HTML string, and then send it down as a prop to the page. The metadata of every post is handled by [`gray-matter`](https://github.com/jonschlinkert/gray-matter) and also sent in props to the page.
+To create the blog posts we use [`remark`](https://github.com/remarkjs/remark) and [`remark-html`](https://github.com/remarkjs/remark-html) to convert the markdown files into an HTML string, and then send it down as a prop to the page. The metadata of every post is handled by [`gray-matter`](https://github.com/jonschlinkert/gray-matter) and also sent in props to the page.
 
 ## Demo