I agree with this - in practice any rule can be broken - but how easily it's broken and whether developers are explicitly told to break it is a process decision. How big a roadblock is your CI putting in the path of developers? If you require e.g. sign-off from a team lead or manager or whoever has "merge anyway" permissions in GitHub, that's more difficult than sign-off from the same reviewer who's reading your code anyway. You can make it easier or harder to break rules and in this case I think it should be so easy to break that there's a codified procedure to do so.