Add smoke test for Google.Cloud.ApiGateway.V1
Add smoke test for Google.Cloud.ApiGateway.V1

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