$ git clone -n https://src.fedoraproject.org/rpms/rubygem-posix-spawn.git /var/lib/mock/f39-build-1458804-33088/root/chroot_tmpdir/scmroot/rubygem-posix-spawn
Cloning into '/var/lib/mock/f39-build-1458804-33088/root/chroot_tmpdir/scmroot/rubygem-posix-spawn'...
$ git fetch origin 0c754b642a199bc2a896bac5ee4f5664681f2e80:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-posix-spawn
 * [new ref]         0c754b642a199bc2a896bac5ee4f5664681f2e80 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0c754b6 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild