Public preview: Test action groups in Azure Monitor

The Azure Monitor test action groups feature enables you to test the notification settings for your alerts. Using the test action group feature enables you to: * Test if notifications are working as expected when creating or updating an action group. * Self-diagnose the cause of notifications not working as expected. [Learn more](https://docs.microsoft.com/azure/azure-monitor/alerts/action-groups). * Azure Monitor * Features * Management * Services * [ Azure Monitor](https://azure.microsoft.com/en-gb/services/monitor/)