jobs:job config contains unknown keys: rules

When running the latest version of GitLab (12.2.3 (13598699)) I get an error from the CI linter about the code I copied from https://docs.gitlab.com/ee/ci/yaml/ Is this a known regression or my private GitLab instance (Community version) doesn't support the rules key?

job:
  script: "echo Hello, Rules!"
  rules:
    - if: '$CI_MERGE_REQUEST_SOURCE_BRANCH =~ /^feature/ && $CI_MERGE_REQUEST_TARGET_BRANCH == "master"' # This rule will be evaluated
      when: always
    - if: '$CI_MERGE_REQUEST_SOURCE_BRANCH =~ /^feature/' # This rule will only be evaluated if the target branch is not "master"
      when: manual
    - if: '$CI_MERGE_REQUEST_SOURCE_BRANCH' # If neither of the first two match but the simple presence does, we set to "on_success" by default