change num worker to 16 for better (#9179)

* change num worker to 16

* adjust num_worker ser_layoutlm_xfund_zh.yml for better performance

configs/kie/layoutlm_series/ser_layoutlm_xfund_zh.yml

@@ -83,7 +83,7 @@ Train:
     shuffle: True
     drop_last: False
     batch_size_per_card: 8
-    num_workers: 4
+    num_workers: 16
 
 Eval:
   dataset: