Multiple definition of CI artifacts allowed, but only last one is honored

Summary

A CI job definition with multiple "artifacts" definition generates no error or warning, even from ci/lint, but only the last one is taken into account. May be a generic yaml-parsing issue.

Steps to reproduce

Use a .gitlab-ci.yml with something like:

build:
  script: ...
  artifacts:
    name: "foo"
    paths:
    - foo
  artifacts:
    name: "bar"
    paths:
    - bar

What is the current bug behavior?

job is accepted, but only "bar" artifacts are available

What is the expected correct behavior?

a warning should be displayed, ci/lint should notify of duplicate keys