notificationType 
  The type of event causing the notification.
- Values: 
- ALERT
- A notification about an event where something was triggered, initiated, reopened, deployed, or a threshold was breached. 
- WARNING
- A notification about an event where an issue is about to arise. For example, something is approaching a threshold. 
- ANNOUNCEMENT
- A notification about an important event. For example, a step in a workflow or escalation path or that a workflow was updated. 
- INFORMATIONAL
- A notification about informational messages. For example, recommendations, service announcements, or reminders.