Remove ci pipeline

.gitlab-ci.yml

-variables:
-  DOCKER_TLS_CERTDIR: "/certs"
-  DOCKER_BASE_IMG: theopirkl/practical-work-manager
-
-docker-build:
-  # Use the official docker image.
-  image: docker:latest
-  stage: build
-  services:
-    - docker:dind
-  script:
-    - echo "$CI_REGISTRY_PASSWORD" | docker login -u "$CI_REGISTRY_USER" --password-stdin
-    - docker image pull $DOCKER_BASE_IMG || true
-    - cd /builds/isc/projects/practical-work-manager
-    - docker build --tag $DOCKER_BASE_IMG .
-    - docker push $DOCKER_BASE_IMG
-  only:
-    changes:
-      - Dockerfile
-      - pwm