$ git clone -n https://src.fedoraproject.org/rpms/perl-Sereal-Encoder.git /var/lib/mock/f41-build-1036538-18736/root/chroot_tmpdir/scmroot/perl-Sereal-Encoder
Cloning into '/var/lib/mock/f41-build-1036538-18736/root/chroot_tmpdir/scmroot/perl-Sereal-Encoder'...
$ git fetch origin 45d652d2940d357fd850b51e120d58144416f79e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Sereal-Encoder
 * [new ref]         45d652d2940d357fd850b51e120d58144416f79e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 45d652d Perl 5.40 rebuild