$ git clone -n https://src.fedoraproject.org/rpms/perl-Unicode-LineBreak.git /var/lib/mock/f41-build-815951-149912/root/chroot_tmpdir/scmroot/perl-Unicode-LineBreak
Cloning into '/var/lib/mock/f41-build-815951-149912/root/chroot_tmpdir/scmroot/perl-Unicode-LineBreak'...
$ git fetch origin 21b1d6d805556b93aaeefe3da315dbd179aaa0c0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Unicode-LineBreak
 * [new ref]         21b1d6d805556b93aaeefe3da315dbd179aaa0c0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21b1d6d Perl 5.40 rebuild