Make 2022 latest version

Author: mbercx

docs/index.rst

@@ -9,9 +9,9 @@ The official home of AiiDA tutorial materials and videos.
    ------
    :column: col-lg-12 pl-0 pr-0
 
-   .. link-button:: https://aiida-tutorials.readthedocs.io/en/tutorial-2021-intro/
+   .. link-button:: https://aiida-tutorials.readthedocs.io/en/tutorial-2022-intro/
       :type: url
-      :text: Latest: 2021 Introductory virtual tutorial
+      :text: Latest: 2022 Introductory virtual tutorial
       :classes: btn-link btn-block stretched-link
 
    -------