add gitlab-ci

.gitlab-ci.yml

+build_docker_image:
+  stage: deploy
+  image:
+    name: gcr.io/kaniko-project/executor:debug
+    entrypoint: [""]
+  rules:
+    - if: '$CI_REGISTRY && $CI_DEFAULT_BRANCH == $CI_COMMIT_BRANCH'
+  script:
+    - mkdir -p /kaniko/.docker
+    - echo "{\"auths\":{\"${CI_REGISTRY}\":{\"auth\":\"$(printf "%s:%s" "${CI_REGISTRY_USER}" "${CI_REGISTRY_PASSWORD}" | base64 | tr -d '\n')\"}}}" > /kaniko/.docker/config.json
+    - /kaniko/executor --force --context "${CI_PROJECT_DIR}" --dockerfile "${CI_PROJECT_DIR}/Dockerfile" --destination "${CI_REGISTRY_IMAGE}:latest"