$ git clone -n https://src.fedoraproject.org/rpms/kdiagram.git /var/lib/mock/f40-build-2241511-53664/root/chroot_tmpdir/scmroot/kdiagram
Cloning into '/var/lib/mock/f40-build-2241511-53664/root/chroot_tmpdir/scmroot/kdiagram'...
$ git fetch origin 39ff33b60fbe000ee08051bf1b320b2ca87373c1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kdiagram
 * [new ref]         39ff33b60fbe000ee08051bf1b320b2ca87373c1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 39ff33b 3.0.1