Fix CircleCI's docker cp
Fix CircleCI's docker cp

according to https://discuss.circleci.com/t/unable-to-use-docker-cp-but-it-worked-2-days-ago/1137/8

rgrunber/docker-client,MarcoLotz/docker-client,spotify/docker-client,MarcoLotz/docker-client,rgrunber/docker-client,spotify/docker-client,bgokden/docker-client,bgokden/docker-client