Some blocks in Ancient City structures can only be covered by sculk veins and can't be converted into a sculk block

Many of the blocks in the ancient cities are intended to be completely taken over by sculk upon world generation. However, Polished Deepslate does not have the #sculk_replaceable_world_gen tag and isn't consistent with how the rest of the full deepslate blocks behave. As a result, Polished Deepslate can only be covered by sculk veins and can't be converted into a sculk block.