$ git clone -n https://src.fedoraproject.org/rpms/rust-rand_core.git /var/lib/mock/f45-build-44232-811/root/chroot_tmpdir/scmroot/rust-rand_core
Cloning into '/var/lib/mock/f45-build-44232-811/root/chroot_tmpdir/scmroot/rust-rand_core'...
$ git fetch origin 69ff3411d7bec34b7ea72a40931e05de30f6cae7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rand_core
 * [new ref]         69ff3411d7bec34b7ea72a40931e05de30f6cae7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 69ff341 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild