$ git clone -n https://src.fedoraproject.org/rpms/perl-Tree-R.git /var/lib/mock/f45-build-27249-622/root/chroot_tmpdir/scmroot/perl-Tree-R
Cloning into '/var/lib/mock/f45-build-27249-622/root/chroot_tmpdir/scmroot/perl-Tree-R'...
$ git fetch origin 37b2b39d96e17af2ce92fe536c0e51e1c4186bcd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Tree-R
 * [new ref]         37b2b39d96e17af2ce92fe536c0e51e1c4186bcd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 37b2b39 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild