Changes

   private static final Gson GSON = new GsonBuilder().setPrettyPrinting().disableHtmlEscaping().create();

   private static final Gson GSON = new GsonBuilder().setPrettyPrinting().disableHtmlEscaping().create();

   protected final Map<Block, LootTable.Builder> lootTables = new HashSet<>();

   protected final Map<Block, LootTable.Builder> lootTables = new HashMap<>();

   public static Map<ResourceLocation, LootTable> tables = new HashMap<>();

   public static Map<ResourceLocation, LootTable> tables = new HashMap<>();

   protected final DataGenerator generator;

   protected final DataGenerator generator;