gitlab-ci: Add prepare state that prebuilds docker image used later
Use --cache to cache intermediate layers Use --single-snapshot to reduce container image size
Signed-off-by: Jan Vesely jano.vesely@gmail.com
Edited by Ján Veselý
Use --cache to cache intermediate layers Use --single-snapshot to reduce container image size
Signed-off-by: Jan Vesely jano.vesely@gmail.com