$ git clone -n https://src.fedoraproject.org/rpms/perl-DBD-MySQL.git /var/lib/mock/f40-build-803199-144204/root/chroot_tmpdir/scmroot/perl-DBD-MySQL
Cloning into '/var/lib/mock/f40-build-803199-144204/root/chroot_tmpdir/scmroot/perl-DBD-MySQL'...
$ git fetch origin c51620557d20da16b82b323fc62e00cdf0fa2e86:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-DBD-MySQL
 * [new ref]         c51620557d20da16b82b323fc62e00cdf0fa2e86 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c516205 5.004 bump (rhbz#2270256)