$ git clone -n https://src.fedoraproject.org/rpms/rust-chrono.git /var/lib/mock/f45-build-40777-776/root/chroot_tmpdir/scmroot/rust-chrono
Cloning into '/var/lib/mock/f45-build-40777-776/root/chroot_tmpdir/scmroot/rust-chrono'...
$ git fetch origin 077158edf370ad45f610744f3e40d11fa26f67c0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-chrono
 * [new ref]         077158edf370ad45f610744f3e40d11fa26f67c0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 077158e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild