Add empty check in transitioning protocol 1.11->1.10

Update to https://github.com/ViaVersion/ViaVersion/pull/3921

common/src/main/java/com/viaversion/viabackwards/protocol/v1_11to1_10/rewriter/BlockItemPacketRewriter1_11.java

@@ -295,7 +295,7 @@ public class BlockItemPacketRewriter1_11 extends LegacyBlockItemRewriter<Clientb
 
     @Override
     public Item handleItemToClient(UserConnection connection, Item item) {
-        if (item == null) return null;
+        if (item == null || item.isEmpty()) return null;
         super.handleItemToClient(connection, item);
 
         CompoundTag tag = item.tag();