$ git clone -n https://src.fedoraproject.org/rpms/rust-rd-util.git /var/lib/mock/f45-build-44388-813/root/chroot_tmpdir/scmroot/rust-rd-util
Cloning into '/var/lib/mock/f45-build-44388-813/root/chroot_tmpdir/scmroot/rust-rd-util'...
$ git fetch origin c63b4efde0ac9e2cc8a5b6de90f82412a33610fa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rd-util
 * [new ref]         c63b4efde0ac9e2cc8a5b6de90f82412a33610fa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c63b4ef Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild