Update metainfo.json

metainfo.json

 {
   "authors": [
-    "John, Doe",
-    "Bob, Alice"
+    "Surname, First names",
+    "Surname, First names"
   ],
   "email": "user@domain.com",
   "title": "Title of the tutorial",
   "description": "In this tutorial we will ...",
   "url": "https://gitlab.mpcdf.mpg.de/nomad-lab/analytics-tutorial-template",
   "link": "https://analytics-toolkit.nomad-coe.eu/hub/user-redirect/notebooks/tutorials/Welcome.ipynb",
-  "created": "",
+  "link_public": "https://analytics-toolkit.nomad-coe.eu/public/user-redirect/notebooks/tutorials/Welcome.ipynb",
   "updated": "",
   "flags":{
-    "isPublic": false,
     "featured": false,
     "top_of_list": false
   },