Extend gitlab-ci.yml to request junit.xml test reports

What does this MR do?

This MR does the following things

1. Allow reports:junit: keyword in gitlab-ci.yml
2. Include artifact_type(archive, junit) and artifact_format(zip, gzip) keyword in job requests of GitLab-runner.
3. Store artifact_type=junit artifact in GitLab-rails

The list of merge requests for the end-goal (Each MR is based on the previous MR)

1. Extend gitlab-ci.yml to request junit.xml test reports
2. Parse junit.xml.gz and calculate the difference between head and base

• CE: Here
• EE: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/6605

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [-] Documentation created/updated => This will be handled in https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/20576
• [-] API support added => https://gitlab.com/gitlab-org/gitlab-ce/issues/49265
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a Backend maintainer
• End-to-end tests pass (package-and-qa manual pipeline job)
• This merge request adds or changes files that require a review from the Database team.

What are the relevant issue numbers?

Related: #46809 (closed)