fix: query for item group listing (#19604)

diff --git a/erpnext/setup/doctype/item_group/item_group.py b/erpnext/setup/doctype/item_group/item_group.py
index 5603f17..f78246f 100644
--- a/erpnext/setup/doctype/item_group/item_group.py
+++ b/erpnext/setup/doctype/item_group/item_group.py
@@ -136,6 +136,7 @@
 		fields = ['name', 'route', 'description', 'image'],
 		filters = dict(
 			show_in_website = 1,
+			parent_item_group = item_group.name,
 			lft = ('>', item_group.lft),
 			rgt = ('<', item_group.rgt),
 		),