endpoints/getting-started-grpc: remove links to docs (#339)
endpoints/getting-started-grpc: remove links to docs (#339)

I removed the links to the quickstarts because they use the bookstore-grpc sample and not this one.
GoogleCloudPlatform/golang-samples,GoogleCloudPlatform/golang-samples,adamyanliev/golang-samples,GoogleCloudPlatform/golang-samples,adamyanliev/golang-samples,adamyanliev/golang-samples,adamyanliev/golang-samples