OSSM-9008 Add link from 2.x to 3.x

Author: gwynnemonahan

modules/ossm-servicemesh-overview.adoc

@@ -11,3 +11,8 @@ Module included in the following assemblies:
 Microservice architectures split the work of enterprise applications into modular services, which can make scaling and maintenance easier. However, as an enterprise application built on a microservice architecture grows in size and complexity, it becomes difficult to understand and manage. {SMProductShortName} can address those architecture problems by capturing or intercepting traffic between services and can modify, redirect, or create new requests to other services.
 
 {SMProductShortName}, which is based on the open source link:https://istio.io/[Istio project], provides an easy way to create a network of deployed services that provides discovery, load balancing, service-to-service authentication, failure recovery, metrics, and monitoring. A service mesh also provides more complex operational functionality, including A/B testing, canary releases, access control, and end-to-end authentication.
+
+[NOTE]
+====
+{SMProductName} 3 is generally available. For more information, see link:https://docs.redhat.com/en/documentation/red_hat_openshift_service_mesh/[{SMProductName} 3.0].
+====