$ git clone -n https://src.fedoraproject.org/rpms/perl-Fedora-Rebuild.git /var/lib/mock/f45-build-23453-597/root/chroot_tmpdir/scmroot/perl-Fedora-Rebuild
Cloning into '/var/lib/mock/f45-build-23453-597/root/chroot_tmpdir/scmroot/perl-Fedora-Rebuild'...
$ git fetch origin 2c801069a9a8333a6ceeb0c225c3d1d7e623e443:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Fedora-Rebuild
 * [new ref]         2c801069a9a8333a6ceeb0c225c3d1d7e623e443 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2c80106 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild