Fix voyage embedding. (#3818)

### What problem does this PR solve?

#3816

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

rag/llm/embedding_model.py

@@ -680,11 +680,10 @@ class VoyageEmbed(Base):
         return np.array(res.embeddings), res.total_tokens
 
     def encode_queries(self, text):
-        res = self.client.embed
         res = self.client.embed(
             texts=text, model=self.model_name, input_type="query"
             )
-        return np.array(res.embeddings), res.total_tokens
+        return np.array(res.embeddings)[0], res.total_tokens
 
 
 class HuggingFaceEmbed(Base):