SPIGOT-4455: ChunkData.getType returns legacy material

By: md_5 <git@md-5.net>

paper-server/src/main/java/org/bukkit/craftbukkit/generator/CraftChunkData.java

@@ -67,7 +67,7 @@ public final class CraftChunkData implements ChunkGenerator.ChunkData {
 
     @Override
     public Material getType(int x, int y, int z) {
-        return getTypeAndData(x, y, z).getItemType();
+        return CraftMagicNumbers.getMaterial(getTypeId(x, y, z).getBlock());
     }
 
     @Override