Passing job:rules downstream and E2E specs for job:rules configuration

What does this MR do?

This MR adds several end-to-end tests for CI job configuration using rules:. It wasn't working correctly as merged and deployed, so I wrote a bunch of specs as diagnostic tools and used that to fix the problem. It now works, and we have several examples where we assert the behavior of pipeline creation given configuration as literal YAML. It serves as both a thorough test and reference material.

Related to: https://gitlab.com/gitlab-org/gitlab-ce/issues/60085 https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/32452

Conformity

• Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
• [-] [Documentation created/updated] This is a fix for an existing documented feature.
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• [-] Database guides
• [-] Separation of EE specific content

Performance and Testing

Several new end-to-end tests have been added to create_pipeline_service_spec.rb

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers