$ git clone -n https://src.fedoraproject.org/rpms/rust-rand_pcg0.3.git /var/lib/mock/f45-build-44258-812/root/chroot_tmpdir/scmroot/rust-rand_pcg0.3
Cloning into '/var/lib/mock/f45-build-44258-812/root/chroot_tmpdir/scmroot/rust-rand_pcg0.3'...
$ git fetch origin b4d3ec78958a4428902915d25035411715505730:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rand_pcg0.3
 * [new ref]         b4d3ec78958a4428902915d25035411715505730 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b4d3ec7 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild