Update .gitlab-ci.yml

.gitlab-ci.yml

 variables:
   HEROKU_APP_NAME: tdt4242-base
   HEROKU_REGISTRY_IMAGE: registry.heroku.com/${HEROKU_APP_NAME}/web
+
 stages:
   - test
-  - build
-  - release
+  - deploy
 
 test:
   image: python:3
@@ -16,29 +16,12 @@ test:
     - pip install -r requirements.txt
     - python manage.py test
 
-image:
-  name: docker/compose:latest
-services:
-    - docker:dind
-
-before_script:
-  - docker version
-  - docker-compose version
-
-build:
-
-  stage: build
+deploy:
+  stage: deploy
+  variables:
+    HEROKU_APP_NAME: tdt4242-base
   script:
-    - apk add --no-cache docker-compose
-    - docker-compose up -d
-
-release:
-  only:
-    - master
-  image: node:10.17-alpine
-  stage: release
-  before_script:
-    - apk add curl bash
-    - curl https://cli-assets.heroku.com/install.sh | sh
-  script:
-    - heroku container:release -a tdt4242-base web
+    - apt-get update -qy
+    - apt-get install -y ruby-dev
+    - gem install dpl
+    - dpl --provider=heroku --app=$HEROKU_APP_NAME --api-key=$HEROKU_AUTH_TOKEN