Search for heavy ZZ resonances in the $$\ell ^+\ell ^-\ell ^+\ell ^-$$ ℓ + ℓ - ℓ + ℓ - and $$\ell ^+\ell ^-\nu \bar{\nu }$$ ℓ + ℓ - ν ν ¯ final states using proton–proton collisions at $$\sqrt{s}= 13$$ s = 13   $$\text {TeV}$$ TeV with the ATLAS detector