ci: add scheduled builds

.gitlab/schedules.gitlab-ci.yml

@@ -0,0 +1,33 @@
+.limit_base_image_publishing:
+    - if: $CI_PIPELINE_SOURCE == "schedule" && $CI_COMMIT_BRANCH == 'main' 
+      when: always
+
+base image:
+  image: docker
+  stage: setup
+  tags: 
+    - gitlab-org-docker
+  inherit:
+    default:
+      - interruptible
+  services:
+    - docker:dind
+  script:
+    - >
+      docker login -u "${CI_REGISTRY_USER}" -p "${CI_JOB_TOKEN}" "${CI_REGISTRY}" && 
+      docker build
+      -t "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:$(grep -o '"version": "[^"]*' "${DEPLOY_DIR}/package.json" | cut -d'"' -f4)"
+      -t "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:latest" "${CI_PROJECT_DIR}/${DEPLOY_DIR}" && 
+      docker push "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}"
+  cache: {} # disable irrelevant cache for this job
+  before_script: [] # do not run irrelevant before script for this job
+  rules: !reference [.limit_base_image_publishing]
+  parallel:
+    matrix:
+      - IMAGE_NAME: node-base
+        DEPLOY_DIR: images/node-base
+      - IMAGE_NAME: node-builder
+        DEPLOY_DIR: images/node-builder
+      - IMAGE_NAME: app-builder
+        DEPLOY_DIR: images/app-builder
+