Persist docker image as an artifact

.gitlab-ci.yml

@@ -82,6 +82,10 @@ build-current-docker-image:
   <<: *docker
   script:
     - docker build -t $CI_REGISTRY_IMAGE:latest -f ./docker/Dockerfile .
+    - docker save $CI_REGISTRY_IMAGE:latest > $CI_REGISTRY_IMAGE:latest
+  artifacts:
+    paths:
+      - $CI_REGISTRY_IMAGE:latest
 
 # When a MR/PR is merged to master
 # take the previous build and publish it to Docker Hub
@@ -91,8 +95,9 @@ build-and-publish-latest-docker-image:
   dependencies:
     - build-current-docker-image
   before_script:
-    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY_URL
+    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD
   script:
+    - docker load -i $CI_REGISTRY_IMAGE:latest
     - docker push $CI_REGISTRY_IMAGE:latest
   only:
     - master