End portal generates too low

[Technically-Hughman]

The end portal generates at 0 1 0, and is too low to allow for a wither cage, and the setting in /carpet doesn't work. For reference, I am playing on 1.16 using the 1.15.2 files.

[skyrising]

The setting is for fixing the vanilla bug where the portal would generate below y=0 and be cut off. I might add a setting for generating the portal at the height it would generate with terrain in the future.