Reproduces bug found for ruby pubsub: googleapis/google-cloud-ruby#3413

To run:

$ docker-compose up -d pubsub_emulator
$ # wait a few seconds for it actually start because it needs to create the topics
$ docker-compose up consumer
$ # make a new tab
$ docker-compose run consumer rake publish_forever

You'll see it fail after around 1k messages erroring in the consumer tab.