Stop pre-pulling the wrong docker base image in travis tests
Stop pre-pulling the wrong docker base image in travis tests

dazuma/ruby-docker,GoogleCloudPlatform/ruby-docker,dazuma/ruby-docker,dazuma/ruby-docker,GoogleCloudPlatform/ruby-docker,GoogleCloudPlatform/ruby-docker,GoogleCloudPlatform/ruby-docker,dazuma/ruby-docker