Inside swamp huts, cat spawn eggs or /summon only produce black cats

The bug

Within the bounds of a swamp hut, only black cats can be spawned with a cat spawn egg in creative mode. Summoning works, but you have to specify the NBT data.

This is very likely done to cause witches' cats in swamp huts to be always black, though this is not always the case due to MC-147659. This restriction, however, this is not necessary.

Expected result

You should be able to summon any cat with a spawn egg or with /summon.