Update modeling_bert.py (#6897)

outptus -> outputs in example of BertForPreTraining

src/transformers/modeling_bert.py

@@ -909,7 +909,7 @@ class BertForPreTraining(BertPreTrainedModel):
             >>> inputs = tokenizer("Hello, my dog is cute", return_tensors="pt")
             >>> outputs = model(**inputs)
 
-            >>> prediction_logits = outptus.prediction_logits
+            >>> prediction_logits = outputs.prediction_logits
             >>> seq_relationship_logits = outputs.seq_relationship_logits
         """
         if "masked_lm_labels" in kwargs: