Update metainfo.json

metainfo.json

@@ -9,6 +9,7 @@
   "url": "https://gitlab.mpcdf.mpg.de/nomad-lab/analytics-exploratory-analysis",
   "link": "https://analytics-toolkit.nomad-coe.eu/hub/user-redirect/notebooks/tutorials/exploratory_analysis_tutorial.ipynb",
   "link_public": "https://analytics-toolkit.nomad-coe.eu/public/user-redirect/notebooks/tutorials/exploratory_analysis_tutorial.ipynb",
+  "link_video": "https://www.youtube.com/watch?v=EJTjF9ehp7k",
   "updated": "2021-01-11",
   "flags":{
     "featured": true,