Updating to include Arc support

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cc: @bwren

Author: austonli

articles/azure-monitor/containers/container-insights-prometheus-integration.md

@@ -21,8 +21,8 @@ Scraping of Prometheus metrics is supported with Kubernetes clusters hosted on:
 
 - Azure Kubernetes Service (AKS)
 - Azure Stack or on-premises
-- Azure Red Hat OpenShift version 3.x
-- Azure Red Hat OpenShift and Red Hat OpenShift version 4.x
+- Azure Arc enabled Kubernetes
+	- Azure Red Hat OpenShift and Red Hat OpenShift version 4.x through cluster connect to Azure Arc
 
 ### Prometheus scraping settings