message: [CI][easy] use default tier for Docker lint job
  Docker build was moved away from CircleCI. With only the lint job
  remaining, we can use the default smaller tier.
  Closes:
  Approved by: andll
diff: @@ -421,9 +421,8 @@ jobs:
  command: terraform validate
  working_directory: terraform/
  lint-docker:
  - machine:
  - image: ubuntu-1604:201903-01
  - resource_class: large
  + executor: audit-executor
  + description: Lint changed Dockerfiles
  steps:
  - checkout
  - run:
  