WebhookEventName
Lifecycle events Cascades can deliver. See `x-webhooks` for each payload.
WebhookEventName is a string that takes one of 6 values, listed under Allowed values.
The machine-readable definition is #/components/schemas/WebhookEventName in
openapi.json;
the example in the right-hand rail is synthesized from the field examples in that spec.
Allowed values
execution.completedexecution.failedadverse_action.triggeredadverse_action.completedadverse_action.failedadverse_action.retry_scheduled