Adaptions to use public docker hub for images

1 job for master in 1 minute and 39 seconds (queued for 4 seconds)
Status Name Job ID Coverage
  Build
failed build #76

00:01:39

 
Name Stage Failure
failed
build Build There is an unknown failure, please try again
Successfully built a95fa62e2125
Successfully tagged ffkabuildenv/buildenv:master
$ docker tag $IMAGE_NAME_UNIQUE $IMAGE_NAME_LATEST
$ docker push $IMAGE_NAME_UNIQUE
The push refers to a repository [docker.io/ffkabuildenv/buildenv]
b681c85419cb: Preparing
a75caa09eb1f: Preparing
denied: requested access to the resource is denied
ERROR: Job failed: exit code 1