$ git clone -n https://src.fedoraproject.org/rpms/rust-once_cell.git /var/lib/mock/f40-build-2682105-67963/root/chroot_tmpdir/scmroot/rust-once_cell
Cloning into '/var/lib/mock/f40-build-2682105-67963/root/chroot_tmpdir/scmroot/rust-once_cell'...
$ git fetch origin eaccd23f798a7b8536b66cdc85b76e691c50bdab:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-once_cell
 * [new ref]         eaccd23f798a7b8536b66cdc85b76e691c50bdab -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eaccd23 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild