Update .gitlab-ci.yml

1 job for master in 9 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
failed #219
build-master

00:00:09

 
Name Stage Failure
failed
build-master Build
WARNING! Your password will be stored unencrypted in /root/.docker/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store

Login Succeeded
$ docker build --pull -t "$CONTAINER_IMAGE" .
invalid argument "" for "-t, --tag" flag: invalid reference format
See 'docker build --help'.
ERROR: Job failed: error executing remote command: command terminated with non-zero exit code: Error executing in Docker Container: 125