$ git clone -n https://src.fedoraproject.org/rpms/rust-rand_core0.9.git /var/lib/mock/f45-build-44237-811/root/chroot_tmpdir/scmroot/rust-rand_core0.9
Cloning into '/var/lib/mock/f45-build-44237-811/root/chroot_tmpdir/scmroot/rust-rand_core0.9'...
$ git fetch origin b874f5820e405d2fc9928713d163357e40420976:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rand_core0.9
 * [new ref]         b874f5820e405d2fc9928713d163357e40420976 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b874f58 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild