Adding Private DNS in the list of resources with the 15 tags limit

Author: vandriot

articles/azure-resource-manager/management/tag-resources.md

@@ -88,7 +88,8 @@ The following limitations apply to tags:
    > * The following Azure resources only support 15 tags:
    >     * Azure Automation
    >     * Azure Content Delivery Network
-   >     * Azure DNS (Zone and A records)
+   >     * Azure Public DNS (Zone and A records)
+   >     * Azure Private DNS (Zone and A records)
    >     * Azure Log Analytics saved search
 
 ## Next steps
@@ -100,4 +101,4 @@ For more information on how to work with tags, see:
 * [Azure PowerShell](tag-resources-powershell.md)
 * [Python](tag-resources-python.md)
 * [ARM templates](tag-resources-templates.md)
-* [Bicep](tag-resources-bicep.md)
+* [Bicep](tag-resources-bicep.md)