Nether and end biomes don't use correct blocks in buffet world type

The bug

Using buffet world type with nether and end biomes generates with stone instead of their correct blocks: netherrack, magma, soul sand, and end stone.

List of affected biomes

Updated to 20w06a

1. nether_wastes
2. soul_sand_valley
3. crimson_forest
4. warped_forest
5. the_end
6. end_barrens
7. end_highlands
8. small_end_islands
9. end_midlands