Document current branch rules precedence

Proposal

This is a follow-up on Document current branch protection precedence r... (#389926 - closed) and the comment to include all branch rules' precedence into the documentation.

  1. Document the precedence rules for all branch rules elements:

    • Allowed to merge (already documented)
    • Allowed to push (already documented)
    • Branch protection codeowner approval required true/false
    • Branch protection allowed to force push true/false
    • Approval rules (normal approval rule / license check / coverage check) - approval required by n
    • Security approval
    • Status checks

  2. Also document, how group level rules for the above setting take precedence over other group level rules or project level rules?

  3. Move the documentation about the precedence of rules to https://docs.gitlab.com/ee/user/project/repository/branches/ (doc/user/project/repository/branches/index.md) because the concept of branches is what these items have in common.

Given that this issue will be worked on after the release of MVC: Branch Rules Overview (&8578 - closed) there may be a better place for this documentation.

Edited by Torsten Linz