$ git clone -n https://src.fedoraproject.org/rpms/rust-beef.git /var/lib/mock/f45-build-40456-772/root/chroot_tmpdir/scmroot/rust-beef
Cloning into '/var/lib/mock/f45-build-40456-772/root/chroot_tmpdir/scmroot/rust-beef'...
$ git fetch origin 7f60f49e50384cae670d22c859b7a4c4b2907a4f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-beef
 * [new ref]         7f60f49e50384cae670d22c859b7a4c4b2907a4f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7f60f49 Regenerate with rust2rpm v28