$ git clone -n https://src.fedoraproject.org/rpms/rust-rand_pcg0.2.git /var/lib/mock/f45-build-44257-812/root/chroot_tmpdir/scmroot/rust-rand_pcg0.2
Cloning into '/var/lib/mock/f45-build-44257-812/root/chroot_tmpdir/scmroot/rust-rand_pcg0.2'...
$ git fetch origin ec0c1e2f19e4919ac6c5a171ed90cd6e8bba7d16:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rand_pcg0.2
 * [new ref]         ec0c1e2f19e4919ac6c5a171ed90cd6e8bba7d16 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ec0c1e2 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild