chore: add more sample data

todolist/integrationtests/src/test/resources/todolist/ui/it-todomodel.json

@@ -9,5 +9,16 @@
       "text" : "Item 2",
       "checked" : false
     } ]
+  },
+  {
+    "name" : "todo1",
+    "deadline" : "2023-10-01T14:53:11",
+    "items" : [ {
+      "text" : "Item 1",
+      "checked" : true
+    }, {
+      "text" : "Item 2",
+      "checked" : false
+    } ]
   } ]
 }
\ No newline at end of file