$ git clone -n https://src.fedoraproject.org/rpms/perl-DBD-MySQL.git /var/lib/mock/f42-build-side-1-3499037-45964/root/chroot_tmpdir/scmroot/perl-DBD-MySQL
Cloning into '/var/lib/mock/f42-build-side-1-3499037-45964/root/chroot_tmpdir/scmroot/perl-DBD-MySQL'...
$ git fetch origin 6271f86571896b2a00b43a52ab34e363a2b708cc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-DBD-MySQL
 * [new ref]         6271f86571896b2a00b43a52ab34e363a2b708cc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6271f86 5.012 bump (rhbz#2359138)