add gitlab ci to build image

.gitlab-ci.yml

@@ -0,0 +1,37 @@
+variables:
+  REGISTRY: registry.vshn.net
+  NAMESPACE: vshn-servalafe-prod
+  OC_IMAGE: docker.io/appuio/oc:v4.16
+
+stages:
+  - build
+  - deploy
+
+.base:
+  stage: build
+  image: docker:stable
+  tags:
+    - dockerbuild_sks
+  services:
+    - name: docker:dind
+      command: ["--mtu=1450"]
+  before_script:
+    - until docker info; do sleep 5; done
+    - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
+
+docker-build-latest:
+  extends: .base
+  script:
+    - docker build --pull -t "$CI_REGISTRY_IMAGE" .
+    - docker push "$CI_REGISTRY_IMAGE"
+  only:
+    - main
+
+deploy:
+  stage: deploy
+  image: $OC_IMAGE
+  script:
+    - echo "todo"
+  environment:
+    name: prod
+    url: https://poc.serva.la/