Ref: update loggings (#11987)

### What problem does this PR solve?

Ref: update loggins

### Type of change

- [x] Refactoring

rag/utils/opendal_conn.py

@@ -41,10 +41,20 @@ def get_opendal_config():
             scheme = opendal_config.get("scheme")
             config_data = opendal_config.get("config", {})
             kwargs = {"scheme": scheme, **config_data}
-        safe_log_keys=['scheme', 'host', 'port', 'database', 'table']
+
+        # Only include non-sensitive keys in logs. Do NOT
+        # add 'password' or any key containing embedded credentials
+        # (like 'connection_string').
+        safe_log_keys = ['scheme', 'host', 'port', 'database', 'table']
         loggable_kwargs = {k: v for k, v in kwargs.items() if k in safe_log_keys}
-        logging.info("Loaded OpenDAL configuration(non sensitive): %s", loggable_kwargs)
-        return kwargs
+        logging.info("Loaded OpenDAL configuration (non sensitive): %s", loggable_kwargs)
+
+        # For safety, explicitly remove sensitive keys from kwargs after use
+        if "password" in kwargs:
+            del kwargs["password"]
+        if "connection_string" in kwargs:
+            del kwargs["connection_string"]
+        return kwargs   
     except Exception as e:
         logging.error("Failed to load OpenDAL configuration from yaml: %s", str(e))
         raise