Update config.json

Generation causes errors of pad token is set to negative. Pad token in model config has to be the one used while tokenization. Related to: https://github.com/huggingface/transformers/issues/25426

config.json

@@ -135,7 +135,7 @@
     "output_attentions": false,
     "output_hidden_states": false,
     "output_scores": false,
-    "pad_token_id": -1,
+    "pad_token_id": 32000,
     "prefix": null,
     "problem_type": null,
     "pruned_heads": {},