fix: fixed catalog json flavor for observability

Author: vbontempi

ibm_catalog.json

@@ -71,7 +71,7 @@
                 "name": "deploy-arch-ibm-observability",
                 "id": "a3137d28-79e0-479d-8a24-758ebd5a0eab-global",
                 "flavors": [
-                  "standard"
+                  "instances"
                 ],
                 "catalog_id": "7a4d68b4-cf8b-40cd-a3d1-f49aff526eb3",
                 "optional": true,