Fix snow accumulating in custom biomes without precipitation (#11854)

paper-server/patches/sources/net/minecraft/world/level/biome/Biome.java.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/level/biome/Biome.java
++++ b/net/minecraft/world/level/biome/Biome.java
+@@ -176,7 +_,7 @@
+     }
+ 
+     public boolean shouldSnow(LevelReader level, BlockPos pos) {
+-        if (this.warmEnoughToRain(pos, level.getSeaLevel())) {
++        if (this.getPrecipitationAt(pos, level.getSeaLevel()) != Precipitation.SNOW) { // Paper - Fixes MC-248212
+             return false;
+         } else {
+             if (level.isInsideBuildHeight(pos.getY()) && level.getBrightness(LightLayer.BLOCK, pos) < 10) {