$ git clone -n https://src.fedoraproject.org/rpms/rust-rd-util.git /var/lib/mock/f40-build-1924426-25102/root/chroot_tmpdir/scmroot/rust-rd-util
Cloning into '/var/lib/mock/f40-build-1924426-25102/root/chroot_tmpdir/scmroot/rust-rd-util'...
$ git fetch origin bd3f76cf852233911fa4e46e4a097086f88561c1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rd-util
 * [new ref]         bd3f76cf852233911fa4e46e4a097086f88561c1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bd3f76c Backport patch to fix version reporting