$ git clone -n https://src.fedoraproject.org/rpms/rust-unic-ucd-version.git /var/lib/mock/f45-build-45904-829/root/chroot_tmpdir/scmroot/rust-unic-ucd-version
Cloning into '/var/lib/mock/f45-build-45904-829/root/chroot_tmpdir/scmroot/rust-unic-ucd-version'...
$ git fetch origin 5b1df62266938b0f875857cc931d187fbbf11e05:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-unic-ucd-version
 * [new ref]         5b1df62266938b0f875857cc931d187fbbf11e05 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5b1df62 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild