adding article to TOC

Author: Sakthi Vetrivel

articles/openshift/toc.yml

@@ -39,6 +39,8 @@
       href: howto-deploy-prometheus.md
     - name: Manage projects in an Azure Red Hat OpenShift cluster
       href: howto-manage-projects.md
+      name: Create a private Azure Red Hat OpenShift cluster
+      href: howto-create-private-cluster.md
     - name: Monitoring and logging
       items:
         - name: Azure Monitor for containers (preview)