$ git clone -n https://src.fedoraproject.org/rpms/rust-bootupd.git /var/lib/mock/f39-build-2566327-62096/root/chroot_tmpdir/scmroot/rust-bootupd
Cloning into '/var/lib/mock/f39-build-2566327-62096/root/chroot_tmpdir/scmroot/rust-bootupd'...
$ git fetch origin fee6df91a65f4d9b0ecfad1eaf5e32242d4271db:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-bootupd
 * [new ref]         fee6df91a65f4d9b0ecfad1eaf5e32242d4271db -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fee6df9 backport patch to support GRUB console.cfg