Add smoke tests for Google.Cloud.Domains.V1Beta1
Add smoke tests for Google.Cloud.Domains.V1Beta1

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