$ git clone -n https://src.fedoraproject.org/rpms/rust-zvariant.git /var/lib/mock/f40-build-2718946-72987/root/chroot_tmpdir/scmroot/rust-zvariant
Cloning into '/var/lib/mock/f40-build-2718946-72987/root/chroot_tmpdir/scmroot/rust-zvariant'...
$ git fetch origin dac292957bf60fbd59884e6a5c268497a0b26946:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-zvariant
 * [new ref]         dac292957bf60fbd59884e6a5c268497a0b26946 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dac2929 Update to version 4.0.2; Fixes RHBZ#2263848