Revert "render ADRs via gitlab pages"

This reverts commit a9ea6120733afd9d75ba8872faa0c5bb41ff3174.

.gitlab-ci.yml

@@ -1,31 +0,0 @@
-# requiring the environment of NodeJS 10
-image: node:10
-
-# add 'node_modules' to cache for speeding up builds
-cache:
-  paths:
-    - node_modules/ # Node modules and dependencies
-
-before_script:
-  - npm install gitbook-cli -g # install gitbook
-  - gitbook fetch 3.2.3 # fetch final stable version
-  - gitbook install # add any requested plugins in book.json
-
-test:
-  stage: test
-  script:
-    - gitbook build ./docs/decisions public # build to public path
-  rules:
-    - if: $CI_COMMIT_REF_NAME != $CI_DEFAULT_BRANCH
-    
-# the 'pages' job will deploy and build your site to the 'public' path
-pages:
-  stage: deploy
-  script:
-    - gitbook build ./docs/decisions public # build to public path
-  artifacts:
-    paths:
-      - public
-    expire_in: 1 week
-  rules:
-    - if: $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH