Add smoke tests for Google.Cloud.Dataflow.V1Beta3
Add smoke tests for Google.Cloud.Dataflow.V1Beta3

googleapis/google-cloud-dotnet,jskeet/google-cloud-dotnet,googleapis/google-cloud-dotnet,jskeet/google-cloud-dotnet,jskeet/google-cloud-dotnet,jskeet/google-cloud-dotnet,jskeet/google-cloud-dotnet,jskeet/gcloud-dotnet,googleapis/google-cloud-dotnet