Fixes an error with getting the golds from the formatted_docs. (#388)

* Fixes an error with getting the golds from the formatted_docs.

* Only taking the first gold element.

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Co-authored-by: Nathan Habib <30601243+NathanHB@users.noreply.github.com>
Co-authored-by: Clémentine Fourrier <22726840+clefourrier@users.noreply.github.com>

Author: 3 people

src/lighteval/metrics/metrics_sample.py

@@ -926,7 +926,7 @@ def compute(self, sample_ids: list[str], responses: list, formatted_docs: list[D
         """
         questions = [formatted_doc.specific["question"] for formatted_doc in formatted_docs]
         options = [formatted_doc.choices for formatted_doc in formatted_docs]
-        golds = [formatted_doc.choices[formatted_doc.gold_index[0]] for formatted_doc in formatted_docs]
+        golds = [formatted_doc.get_golds()[0] for formatted_doc in formatted_docs]
         predictions = [response[0].result[0] for response in responses]
 
         scores, messages, judgements = self.judge.evaluate_answer_batch(questions, predictions, options, golds)