fix: fix the wording for Observability add-on descrption (#459)

Author: ocofaigh

ibm_catalog.json

@@ -610,7 +610,7 @@
             },
             {
               "name": "deploy-arch-ibm-observability",
-              "description": "Enable to provisions and configures IBM Cloud Monitoring, Activity Tracker, and Log Analysis services for analysing events generated from the Events Notification instance.",
+              "description": "Enable to provision and configure IBM Cloud Logs, Cloud Monitoring, Metrics routing and Activity Tracker event routing for analysing logs and metrics generated by the Event Notifications instance.",
               "flavors": [
                 "instances"
               ],