$ git clone -n https://src.fedoraproject.org/rpms/perl-DB_File.git /var/lib/mock/f41-build-816872-150476/root/chroot_tmpdir/scmroot/perl-DB_File
Cloning into '/var/lib/mock/f41-build-816872-150476/root/chroot_tmpdir/scmroot/perl-DB_File'...
$ git fetch origin d8d7f58c9ba58e6cb43353c21b59a4820597cd08:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-DB_File
 * [new ref]         d8d7f58c9ba58e6cb43353c21b59a4820597cd08 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d8d7f58 Perl 5.40 re-rebuild of bootstrapped packages