Details with code examples have been covered here: coredns/coredns#7435 (comment)
Presumably this is the project where the change should be done. It may also require some platform conditional if supporting other platforms than Linux.
Technically this only affects the Docker container builds that apply file-based capabilities via setcap to support non-root process on kubernetes, which AFAIK shouldn't be required anymore (but is not yet default, thus requires opt-in by the k8s admin).