$ git clone -n https://src.fedoraproject.org/rpms/rust-lapp.git /var/lib/mock/f45-build-42821-796/root/chroot_tmpdir/scmroot/rust-lapp
Cloning into '/var/lib/mock/f45-build-42821-796/root/chroot_tmpdir/scmroot/rust-lapp'...
$ git fetch origin c20bac06362dd1c58231b8cccfa8e6f4c83a0c93:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-lapp
 * [new ref]         c20bac06362dd1c58231b8cccfa8e6f4c83a0c93 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c20bac0 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild