Document new report types

What does this MR do?

• Add new report types to .gitlab-ci.yml documentation
• Update examples with old and new syntax
• Sync with EE docs to avoid conflicts
• Make content consistent between features

There is a corresponding CE MR: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/22828

Related issues

gitlab-org/gitlab-ce#52323

Author's checklist

• Apply the correct labels and milestone
• Crosslink the document from the higher-level index
• Crosslink the document from other subject-related docs
• Feature moving tiers? Make sure the change is also reflected in features.yml
• Correctly apply the product badges and tiers
• Port the MR to EE (or backport from CE): always recommended, required when the ee-compat-check job fails

Review checklist

• Your team's review (required)
• PM's review (recommended, but not a blocker)
• Technical writer's review (required)
• Merge the EE-MR first, CE-MR afterwards