Adding author usernames (#1249)

Author: ikurecic

demonstrations/tutorial_QUBO.metadata.json

@@ -2,11 +2,11 @@
     "title": "Quadratic Unconstrained Binary Optimization",
     "authors": [
         {
-            "id": "alejandro_montanez"
+            "username": "alejomonbar"
         }
     ],
     "dateOfPublication": "2024-02-29T00:00:00+00:00",
-    "dateOfLastModification": "2024-10-07T00:00:00+00:00",
+    "dateOfLastModification": "2024-11-06T00:00:00+00:00",
     "categories": [
         "Optimization"
     ],

demonstrations/tutorial_learning_few_data.metadata.json

@@ -8,11 +8,11 @@
             "id": "luis_mantilla_calderon"
         },
         {
-            "id": "maurice_weber"
+            "username": "mauriceweber"
         }
     ],
     "dateOfPublication": "2022-08-29T00:00:00+00:00",
-    "dateOfLastModification": "2024-10-07T00:00:00+00:00",
+    "dateOfLastModification": "2024-10-29T00:00:00+00:00",
     "categories": [
         "Quantum Machine Learning"
     ],