$ git clone -n https://src.fedoraproject.org/rpms/perl-File-Fetch.git /var/lib/mock/f43-perl-60945233-6586545/root/chroot_tmpdir/scmroot/perl-File-Fetch
Cloning into '/var/lib/mock/f43-perl-60945233-6586545/root/chroot_tmpdir/scmroot/perl-File-Fetch'...
$ git fetch origin 743152960322bbf3eed545919209fa26f248d5d1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-File-Fetch
 * [new ref]         743152960322bbf3eed545919209fa26f248d5d1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7431529 Perl 5.42 rebuild