Use `gcloud app` instead of `gcloud preview app`
Use `gcloud app` instead of `gcloud preview app`

GoogleCloudPlatform/pubsub-shout-csharp,GoogleCloudPlatform/pubsub-shout-csharp,GoogleCloudPlatform/pubsub-shout-csharp,GoogleCloudPlatform/pubsub-shout-csharp