Reusing configuration in GitLab pipelines

Let's suppose that the have 2 following jobs:

deploy to staging:
    stage: deploy staging
    environment: staging
    image:
        name: amazon/aws-cli:2.4.11
        entrypoint: [""]
    rules:
        - if: $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH
    script:
        - aws -version
        - aws s3 sync build s3://$AWS_S3_BUCKET --delete
        - curl $CI_ENVIRONMENT_URL | grep "React App"
deploy to production:
    stage: deploy production
    environment: production
    image:
        name: amazon/aws-cli:2.4.11
        entrypoint: [""]
    rules:
        - if: $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH
    script:
        - aws -version
        - aws s3 sync build s3://$AWS_S3_BUCKET --delete
        - curl $CI_ENVIRONMENT_URL | grep "React App"

The above code could be written in another way:

.deploy:
    image:
        name: amazon/aws-cli:2.4.11
        entrypoint: [""]
    rules:
        - if: $CI_COMMIT_REF_NAME == $CI_DEFAULT_BRANCH
    script:
        - aws -version
        - aws s3 sync build s3://$AWS_S3_BUCKET --delete
        - curl $CI_ENVIRONMENT_URL | grep "React App"
deploy to staging:
    stage: deploy staging
    environment: staging
    extends: .deploy
deploy to production:
    stage: deploy production
    environment: production
    extends: .deploy