$ git clone -n https://src.fedoraproject.org/rpms/perl-Time-Duration.git /var/lib/mock/f45-build-27120-621/root/chroot_tmpdir/scmroot/perl-Time-Duration
Cloning into '/var/lib/mock/f45-build-27120-621/root/chroot_tmpdir/scmroot/perl-Time-Duration'...
$ git fetch origin c61ec4a45bbd7edcc1051bd49c8dd0f491c0626e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Time-Duration
 * [new ref]         c61ec4a45bbd7edcc1051bd49c8dd0f491c0626e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c61ec4a Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild