Update generation_config.json

generation_config.json

@@ -7,6 +7,7 @@
   "top_k": 40,
   "do_sample": true,
   "max_new_tokens": 512,
+  "num_beams": 3,
   "repetition_penalty": 1.1,
   "no_repeat_ngram_size": 5
 }