fix: Set hub_url in Hub Settings

- add patch to set the value
diff --git a/erpnext/hub_node/api.py b/erpnext/hub_node/api.py
index 441d30b..74219da 100644
--- a/erpnext/hub_node/api.py
+++ b/erpnext/hub_node/api.py
@@ -180,9 +180,9 @@
 
 	# read-only connection
 	if read_only:
-		hub_connection = FrappeClient(frappe.conf.hub_url)
+		hub_url = frappe.db.get_single_value('Hub Settings', 'hub_url')
+		hub_connection = FrappeClient(hub_url)
 		return hub_connection
 
-
 def get_field_mappings():
 	return []