Fixed infinity exception SCORE() / SCORE_FACTORS() requires Fusion or MATCH TEXT or MATCH TENSOR (#4110)

### What problem does this PR solve?

Fixed infinity exception SCORE() / SCORE_FACTORS() requires Fusion or
MATCH TEXT or MATCH TENSOR. Close #4109

### Type of change

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

rag/utils/infinity_conn.py

@@ -247,9 +247,12 @@ class InfinityConnection(DocStoreConnection):
         db_instance = inf_conn.get_database(self.dbName)
         df_list = list()
         table_list = list()
-        for essential_field in ["id", "score()", "pagerank_fea"]:
+        for essential_field in ["id"]:
             if essential_field not in selectFields:
                 selectFields.append(essential_field)
+        if matchExprs:
+            for essential_field in ["score()", "pagerank_fea"]:
+                selectFields.append(essential_field)
 
         # Prepare expressions common to all tables
         filter_cond = None
@@ -337,7 +340,8 @@ class InfinityConnection(DocStoreConnection):
                 df_list.append(kb_res)
         self.connPool.release_conn(inf_conn)
         res = concat_dataframes(df_list, selectFields)
-        res = res.sort(pl.col("SCORE") + pl.col("pagerank_fea"), descending=True, maintain_order=True)
+        if matchExprs:
+            res = res.sort(pl.col("SCORE") + pl.col("pagerank_fea"), descending=True, maintain_order=True)
         res = res.limit(limit)
         logger.debug(f"INFINITY search final result: {str(res)}")
         return res, total_hits_count