$ git clone -n https://src.fedoraproject.org/rpms/kdiagram.git /var/lib/mock/f40-build-2076025-49523/root/chroot_tmpdir/scmroot/kdiagram
Cloning into '/var/lib/mock/f40-build-2076025-49523/root/chroot_tmpdir/scmroot/kdiagram'...
$ git fetch origin 1fc4f0898069cb090e8171e3b347e5d8bb44831a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kdiagram
 * [new ref]         1fc4f0898069cb090e8171e3b347e5d8bb44831a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1fc4f08 3.0.0