Docker pull always fails.

Summary

For any build today in a private project of mine, gitlab runners will fail to pull the public "docker:latest" tag from docker hub.

Steps to reproduce

• Retry job #62558436

This is the build stage:

deploy_staging:
  stage: deploy
  image: docker:latest
  services:
    - docker:dind
  dependencies: []
  script:
    - ls

What is the current bug behavior?

Running with gitlab-runner 10.6.0 (a3543a27)
  on docker-auto-scale 72989761
Using Docker executor with image docker:latest ...
Starting service docker:dind ...
Pulling docker image docker:dind ...
Using docker image sha256:6fc95ba0a7762a13d4db830df765c534ece1963f11093dfb8940f525b63084c3 for docker:dind ...
Waiting for services to be up and running...
Pulling docker image docker:latest ...
ERROR: Preparation failed: Error: No such image: docker:latest
Will be retried in 3s ...
Using Docker executor with image docker:latest ...
Starting service docker:dind ...
Pulling docker image docker:dind ...
Using docker image sha256:6fc95ba0a7762a13d4db830df765c534ece1963f11093dfb8940f525b63084c3 for docker:dind ...
Waiting for services to be up and running...
Pulling docker image docker:latest ...
ERROR: Preparation failed: Error: No such image: docker:latest
Will be retried in 3s ...
Using Docker executor with image docker:latest ...
Starting service docker:dind ...
Pulling docker image docker:dind ...
Using docker image sha256:6fc95ba0a7762a13d4db830df765c534ece1963f11093dfb8940f525b63084c3 for docker:dind ...
Waiting for services to be up and running...
Pulling docker image docker:latest ...
ERROR: Preparation failed: Error: No such image: docker:latest
Will be retried in 3s ...
ERROR: Job failed (system failure): Error: No such image: docker:latest

What is the expected correct behavior?

The job should pull the image as it always did historically:

Running with gitlab-runner 10.6.0 (a3543a27)
  on docker-auto-scale fa6cab46
Using Docker executor with image docker:latest ...
Starting service docker:dind ...
Pulling docker image docker:dind ...
Using docker image sha256:a5d94acbd847eb490dff15af12eb4bd9a7058400c21a3bb65d8f6a18a79c484d for docker:dind ...
Waiting for services to be up and running...
Pulling docker image docker:latest ...
Using docker image sha256:cf0bbd4500c6d7c8dc438c69a9cf381e4461c47a5d0977e385e477a9976b1a2d for docker:latest ...
Running on runner-fa6cab46-project-6010166-concurrent-0 via runner-fa6cab46-srm-1523452340-6f543765...

Output of checks

This bug happens on GitLab.com