feat(ci): Add multi-arch Docker build support with buildx

Author: editheman

.gitlab-ci.yml

@@ -12,14 +12,15 @@
 
 docker-build:
   # Use the official docker image.
-  image: docker:cli
+  image: docker:latest
   stage: build
   services:
     - docker:dind
   variables:
     DOCKER_IMAGE_NAME: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
   before_script:
-    - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
+    - echo "$CI_REGISTRY_PASSWORD" | docker login -u "$CI_REGISTRY_USER" --password-stdin $CI_REGISTRY
+    - docker run --privileged --rm tonistiigi/binfmt --install all
   # All branches are tagged with $DOCKER_IMAGE_NAME (defaults to commit ref slug)
   # Default branch is also tagged with `latest`
   script: