$ git clone -n https://src.fedoraproject.org/rpms/rust-mesa3d_util.git /var/lib/mock/f45-build-43247-801/root/chroot_tmpdir/scmroot/rust-mesa3d_util
Cloning into '/var/lib/mock/f45-build-43247-801/root/chroot_tmpdir/scmroot/rust-mesa3d_util'...
$ git fetch origin be8df00c58f070639a29705c06d1d2ecfd0fe955:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-mesa3d_util
 * [new ref]         be8df00c58f070639a29705c06d1d2ecfd0fe955 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at be8df00 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild