$ git clone -n https://src.fedoraproject.org/rpms/rust-num-rational0.3.git /var/lib/mock/f45-build-43446-803/root/chroot_tmpdir/scmroot/rust-num-rational0.3
Cloning into '/var/lib/mock/f45-build-43446-803/root/chroot_tmpdir/scmroot/rust-num-rational0.3'...
$ git fetch origin 56b204ee818ba7369f3d077c8db807aaf21d2757:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-num-rational0.3
 * [new ref]         56b204ee818ba7369f3d077c8db807aaf21d2757 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 56b204e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild