Update Codespaces link

Use the link that directly shows info about Codespaces, because it's a bit confusing when the user clicks on <kbd>GitHub Codespaces</kbd> and is directed to github.com.

Author: filiptronicek

README.md

@@ -6,7 +6,7 @@
 
 ## What is this?
 
-This project provides a version of VS Code that runs a server on a remote machine and allows access through a modern web browser. It's based on the very same architecture used by [Gitpod](https://www.gitpod.io) or [GitHub Codespaces](https://github.com) at scale.
+This project provides a version of VS Code that runs a server on a remote machine and allows access through a modern web browser. It's based on the very same architecture used by [Gitpod](https://www.gitpod.io) or [GitHub Codespaces](https://github.com/features/codespaces) at scale.
 
 <img width="1624" alt="Screenshot 2021-09-02 at 08 39 26" src="https://user-images.githubusercontent.com/372735/131794918-d6602646-4d67-435b-88fe-620a3cc0a3aa.png">