"m2l4q for gluon-gluon fusion, llWW, mA 550 mH 300" of "Search for a heavy Higgs boson decaying into a $Z$ boson and another heavy Higgs boson in the $\ell\ell bb$ and $\ell\ell WW$ final states in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector"