use new api

inventory_provider/tasks/worker.py

@@ -111,8 +111,8 @@ def snmp_refresh_interfaces(self, hostname, community):
 
 @app.task(bind=InventoryTask)
 def netconf_refresh_config(self, hostname):
-    InventoryTask.save_key(
+    InventoryTask.save_key_etree(
         hostname,
         "netconf",
-        netconf.load_config_str(hostname, InventoryTask.config["ssh"]))
+        netconf.load_config(hostname, InventoryTask.config["ssh"]))