Make alpine based image the default and remove ubuntu image

.circleci/config.yml

@@ -12,15 +12,6 @@ workflows:
   # Defines workflow for when to build the different Docker images
   build-docker-images:
     jobs:
-      - build-ubuntu-image:
-          context: dockerhub
-          filters:
-            branches:
-              only:
-                - dev
-                - master
-            tags:
-              only: /^\d+\.\d+.*/
       - build-alpine-image:
           context: dockerhub
           filters:
@@ -51,25 +42,6 @@ workflows:
 
 # Job definitions, used by the workflows.
 jobs:
-  build-ubuntu-image:
-    environment:
-      IMAGE_NAME: haugene/transmission-openvpn
-    docker:
-      - image: circleci/buildpack-deps:stretch
-    steps:
-      - checkout
-      - setup_remote_docker
-      - calculate-tag-name:
-          distro: ubuntu
-      - run:
-          name: Build Docker image
-          command: docker build -t $IMAGE_NAME:$IMAGE_TAG .
-      - run:
-          name: Login to Docker Hub
-          command: echo $DOCKER_PASS | docker login -u $DOCKER_USER --password-stdin
-      - run:
-          name: Push image
-          command: docker push $IMAGE_NAME:$IMAGE_TAG
 
   build-alpine-image:
     environment: