fix: fix bug when not using knowledge_distilation in fine-tuning embedder

Author: yjoonjang

FlagEmbedding/abc/finetune/embedder/AbsDataset.py

@@ -416,8 +416,9 @@ def _create_batch_data(self, batch_raw_data):
 
             passages.extend(tmp_passages)
 
-            if len(teacher_scores) > 0 and len(passages) > 0:
-                assert len(teacher_scores) == len(passages)
+            if teacher_scores is not None:
+                if len(teacher_scores) > 0 and len(passages) > 0:
+                    assert len(teacher_scores) == len(passages)
 
         return queries, passages, teacher_scores