fixed missing torch module import (#4305)

fixed missing torch module import in example usage code

model_cards/lserinol/bert-turkish-question-answering/README.md

@@ -17,6 +17,7 @@ nlp({
 
 ```python
 from transformers import AutoTokenizer, AutoModelForQuestionAnswering
+import torch
 
 tokenizer = AutoTokenizer.from_pretrained("lserinol/bert-turkish-question-answering")
 model = AutoModelForQuestionAnswering.from_pretrained("lserinol/bert-turkish-question-answering")