Create/Update assets for version 1.21-pre1

data/minecraft/structure/bastion/hoglin_stable/stairs/_list.json

@@ -0,0 +1 @@
+{"directories":[],"files":["stairs_1_0.nbt","stairs_1_1.nbt","stairs_1_2.nbt","stairs_1_3.nbt","stairs_1_4.nbt","stairs_2_0.nbt","stairs_2_1.nbt","stairs_2_2.nbt","stairs_2_3.nbt","stairs_2_4.nbt","stairs_3_0.nbt","stairs_3_1.nbt","stairs_3_2.nbt","stairs_3_3.nbt","stairs_3_4.nbt"]}