Skip stripping metadata from empty stacks (#6973)

patches/server/Hide-unnecessary-itemmeta-from-clients.patch

@@ -43,7 +43,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      }
  
 +    public static void stripMeta(ItemStack itemStack, @org.jetbrains.annotations.Nullable Level level) {
-+        if (itemStack.getTag() != null) {
++        if (itemStack.getTag() != null && !itemStack.isEmpty()) {
 +            CompoundTag nbt = itemStack.getTag();
 +            if (level != null && level.paperConfig.hideDurabilityFromClients) {
 +                // Only show damage values for elytra's, since they show a different texture when broken.