abuild: remove host uid/gid from pkg
Names are kept but uid/gid are removed:
$ tar -tvf alpine-baselayout-data-3.6.5-r0.apk etc/shadow
-rw-r----- root/shadow 259 2024-05-06 09:38 etc/shadow
$ tar --numeric-owner -tvf alpine-baselayout-data-3.6.5-r0.apk etc/shadow
-rw-r----- 0/0 259 2024-05-06 09:38 etc/shadow
Closes #10127 (closed)