$ git clone -n https://src.fedoraproject.org/rpms/rust-spin_on.git /var/lib/mock/f45-build-45119-821/root/chroot_tmpdir/scmroot/rust-spin_on
Cloning into '/var/lib/mock/f45-build-45119-821/root/chroot_tmpdir/scmroot/rust-spin_on'...
$ git fetch origin cead1d8fba2a353e1edc306a51e1e74a9cd282ee:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-spin_on
 * [new ref]         cead1d8fba2a353e1edc306a51e1e74a9cd282ee -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cead1d8 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild