$ git clone -n https://src.fedoraproject.org/rpms/octave-control.git /var/lib/mock/f40-build-1965479-25205/root/chroot_tmpdir/scmroot/octave-control
Cloning into '/var/lib/mock/f40-build-1965479-25205/root/chroot_tmpdir/scmroot/octave-control'...
$ git fetch origin 2b844ca9f2b51f6619e83b2188e0e46196190a7a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/octave-control
 * [new ref]         2b844ca9f2b51f6619e83b2188e0e46196190a7a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2b844ca renamed file