Remove unused gitlab ci config

.gitlab-ci.yml

-image: docker:stable
-
-#services:
-#  - docker:dind
-
-variables:
-  IMAGE_TAG: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME
-
-before_script:
-  - docker login -u gitlab-ci-token -p $CI_JOB_TOKEN $CI_REGISTRY
-
-build:
-  stage: build
-  script:
-    - docker build --force-rm -t $IMAGE_TAG .
-    - docker push $IMAGE_TAG