Draft: Gitlab ci image build

sync ci image build to fit the manual builds https://reseed-documentation.rd.ruhr-uni-bochum.de/system/deployment/2_image_building/

.gitlab-ci.yml

-image: docker:stable
+default:
+  before_script:
+    - docker infoimage: docker:stable
+
 image: ruby:2.7.8-alpine
 
 stages: