Login to the image registry first... (Although I thought I didn't need to)

.gitlab-ci.yml

+
+before_script:
+  - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+
 build:
   image:
     name: gitlab-registry.light.kow.is/kowis-projects/java8openjfxcontainer/openjdk-openjfx8