message: ci: use comma for separating docker tags
diff: @@ -38,7 +38,7 @@ jobs:
  TAGS="${DOCKER_IMAGE}:${VERSION}"
  # mark the latest on release
  if [[ $VERSION =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
  - TAGS="$TAGS\n${DOCKER_IMAGE}:latest"
  + TAGS="$TAGS,${DOCKER_IMAGE}:latest"
  fi
  echo "::set-output name=tags::${TAGS}"
  