Only CODEOWNERS on default branch affect MR approvals
What does this MR do?
Adds a note in documentation that only the CODEOWNERS file on the default branch affects MR approvals. A change in a non-default branch will not affect approvals until/unless it is merged to the default/master branch.
@anton and I discovered this while testing approvals for a customer in https://gitlab.zendesk.com/agent/tickets/131462.