Also fixing docker file to ensure service account is copied.
diff --git a/tools/dockerfile/grpc_python/Dockerfile b/tools/dockerfile/grpc_python/Dockerfile
index 62ef785..aa29685 100644
--- a/tools/dockerfile/grpc_python/Dockerfile
+++ b/tools/dockerfile/grpc_python/Dockerfile
@@ -66,5 +66,8 @@
# Add a cacerts directory containing the Google root pem file, allowing the interop client to access the production test instance
ADD cacerts cacerts
+# Add a service_account directory containing the auth creds file
+ADD service_account service_account
+
# Specify the default command such that the interop server runs on its known testing port
CMD ["/bin/bash", "-l", "-c", "python2.7 -m interop.server --use_tls --port 8050"]