$ git clone -n https://src.fedoraproject.org/rpms/rust-untrusted.git /var/lib/mock/f45-build-45990-830/root/chroot_tmpdir/scmroot/rust-untrusted
Cloning into '/var/lib/mock/f45-build-45990-830/root/chroot_tmpdir/scmroot/rust-untrusted'...
$ git fetch origin 9427d455447fab9a35fce45c4a726c3aae9e90c3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-untrusted
 * [new ref]         9427d455447fab9a35fce45c4a726c3aae9e90c3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9427d45 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild