Fix incorrect biome color representation (#66)

Author: SuperGamerTron

mc/1.21.11/src/main/java/dev/u9g/minecraftdatagenerator/generators/BiomesDataGenerator.java

@@ -96,7 +96,8 @@ public static JsonObject generateBiomeInfo(Registry<Biome> registry, Biome biome
         EnvironmentAttributeMap.Entry<Integer, ?> skyColorEntry = biome.getAttributes().get(EnvironmentAttributes.SKY_COLOR);
         int skyColor = 0;
         if (skyColorEntry != null && skyColorEntry.argument() instanceof Integer) {
-            skyColor = (Integer) skyColorEntry.argument();
+            // convert to RGB
+            skyColor = (Integer) skyColorEntry.argument() & 0xFFFFFF;
         }
         biomeDesc.addProperty("color", skyColor);
         //biomeDesc.addProperty("rainfall", biome.getDownfall());// - removed in 1.19.4