Update models README.md

7 jobs for 13-preparar-para-conexao-com-postgres in 9 seconds (queued for 2 seconds)
Name Stage Failure
failed
build Build There has been a runner system failure, please try again

ERROR: The docker:stable-git is not present on list of allowed images
- ubuntu:*
- i386/ubuntu:*

Please check runner's configuration: http://doc.gitlab.com/ci/docker/using_docker_images.html#overwrite-image-and-services
ERROR: Preparation failed: invalid image
Will be retried in 3s ...
ERROR: Job failed (system failure): invalid image