$ git clone -n https://src.fedoraproject.org/rpms/rust-pep508_rs.git /var/lib/mock/f45-build-43788-805/root/chroot_tmpdir/scmroot/rust-pep508_rs
Cloning into '/var/lib/mock/f45-build-43788-805/root/chroot_tmpdir/scmroot/rust-pep508_rs'...
$ git fetch origin eb6e46df61b71a45ed0fc7b1785cbd7cac39ab6b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-pep508_rs
 * [new ref]         eb6e46df61b71a45ed0fc7b1785cbd7cac39ab6b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eb6e46d Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild