Update catalog information

catalog.json

@@ -1139,7 +1139,7 @@
             "latest_version": "1.0.0",
             "latest_app_version": "9.5.3",
             "latest_human_version": "9.5.3_1.0.0",
-            "last_update": null,
+            "last_update": "2023-06-12 13:28:37",
             "name": "grafana",
             "recommended": false,
             "title": "Grafana",