We don't want to accidentally introduce these again since we
deliberately switched all packages to maintainer variables. While this
probably could be made part of apkbuild-lint eventually, the Alpine TSC
hasn't yet made a decision about whether to switch to maintainer
variables or not to the best of my knowledge so I don't think it can be
made upstream policy yet. Make it a clear downstream policy via this
check for now as such.
Signed-off-by: Stefan Hansson <newbyte@postmarketos.org>
Part-of: <https://gitlab.postmarketos.org/postmarketOS/pmaports/-/merge_requests/7824>