Fixed translation metric

src/custom_tasks/translation_task.py

@@ -49,7 +49,7 @@ translation_task = LightevalTaskConfig(
     hf_subset="default",
     hf_avail_splits=["en2he", "he2en"],
     evaluation_splits=["en2he", "he2en"],
-    metric=['sentence_bleu', 'bleu_1', 'bleu_4'],
+    metric=['sentence_bleu'],
     stop_sequence=['\n'],
     generation_size=220
 )