.gitlab-ci.yml: Build Docker Image

.gitlab-ci.yml

# This file is a template, and might need editing before it works on your project.
# Official docker image.
image: docker:latest
services:
  - docker:dind
build:
  stage: build
  script:
    # $DOCKERHUB_USER is NOT your email address, it's your username!
    - docker login -u "$DOCKERHUB_USER" -p "$DOCKERHUB_PASSWORD"
    - docker build --pull -t $DOCKERHUB_USER/image-name .
    - docker push $DOCKERHUB_USER/image-name