How to configure Gitlab CI to macos cloud runner

I am configuring Gitlab CI and want to use GitLab macOS cloud runner. I have followed the guide and added in yml file but still it build through my local machine. Below is my yml file and not sure how can hook macOS cloud runner.

I would appreciate if anyone uses macOS cloud and help me out with configuration.

.macos_buildcloud_runners:
  tags:
    - shared-macos-amd64
  image: macos-11-xcode-12

stages:
  - build

before_script:
  - users
  - export LANG=en_US.UTF-8

build_project:
  extends:  
    - .macos_buildcloud_runners
  stage: build
  cache:
    key:
      files:
        - yarn.lock
    paths:
      - .yarn-cache/
    key:
       files:
         -ios/Podfile.lock
    paths:
      - .pod-cache/
    key:
       files:
         - Gemfile.lock
    paths:
      - vendor/bundle
    
  tags:
    - beta-deployment
    - beta-build
  rules:
    - if: '$CI_COMMIT_BRANCH == $CI_DEFAULT_BRANCH'
      when: always
    - if: '$CI_COMMIT_BRANCH == "feature/gitlab-ci"'
      when: always
    - when: never

  script:
    - cd .. && yarn install --cache-folder .yarn-cache
    - cd ios && gem install bundler
    - bundle install
    - pod install
    - bundle exec fastlane beta