Update versions to match grpc-java docs
Update versions to match grpc-java docs

The new changes match versions in:

https://github.com/grpc/grpc-java/blob/master/README.md
googlearchive/cloud-pubsub-samples-java,GoogleCloudPlatform/cloud-pubsub-samples-java,googlearchive/cloud-pubsub-samples-java,GoogleCloudPlatform/cloud-pubsub-samples-java,GoogleCloudPlatform/cloud-pubsub-samples-java,googlearchive/cloud-pubsub-samples-java