Set upstream timeout for envoy in echo example
Set upstream timeout for envoy in echo example

Without this, streaming calls fail after a few seconds because envoy terminates the connection to the gRPC upstream.
grpc/grpc-web,grpc/grpc-web,grpc/grpc-web,grpc/grpc-web,grpc/grpc-web,grpc/grpc-web,grpc/grpc-web