Invalid CI-configuration with Cobertura report

Summary

Pipeline configurations reports config contains unknown keys: cobertura, making it so that no pipelines with coverage reporting can be run.

Steps to reproduce

Paste the example from https://docs.gitlab.com/ee/user/project/merge_requests/test_coverage_visualization.html#gradle-example into the CI-editor.

test-jdk11:
  stage: test
  image: gradle:6.6.1-jdk11
  script:
    - 'gradle test jacocoTestReport' # jacoco must be configured to create an xml report
  artifacts:
    paths:
      - build/jacoco/jacoco.xml

coverage-jdk11:
  # Must be in a stage later than test-jdk11's stage.
  # The `visualize` stage does not exist by default.
  # Please define it first, or chose an existing stage like `deploy`.
  stage: visualize
  image: registry.gitlab.com/haynes/jacoco2cobertura:1.0.7
  script:
    # convert report from jacoco to cobertura, using relative project path
    - python /opt/cover2cover.py build/jacoco/jacoco.xml $CI_PROJECT_DIR/src/main/java/ > build/cobertura.xml
  needs: ["test-jdk11"]
  artifacts:
    reports:
      cobertura: build/cobertura.xml

Example Project

This can be done anywhere

What is the current bug behavior?

Gitlab reports the pipeline as invalid.

What is the expected correct behavior?

The pipeline should not be reported as invalid and the cobertura report should be enabled to allow inline code-coverage feedback.

Relevant logs and/or screenshots

See above.

Output of checks

This bug happens on GitLab.com

Results of GitLab environment info

Not applicable.

Results of GitLab application Check