fix: allow_items_not_in_stock should be evaluated (#19398)

diff --git a/erpnext/shopping_cart/cart.py b/erpnext/shopping_cart/cart.py
index f850bc1..a4c10cf 100644
--- a/erpnext/shopping_cart/cart.py
+++ b/erpnext/shopping_cart/cart.py
@@ -66,7 +66,7 @@
 	from erpnext.selling.doctype.quotation.quotation import _make_sales_order
 	sales_order = frappe.get_doc(_make_sales_order(quotation.name, ignore_permissions=True))
 
-	if not cart_settings.allow_items_not_in_stock:
+	if not cint(cart_settings.allow_items_not_in_stock):
 		for item in sales_order.get("items"):
 			item.reserved_warehouse, is_stock_item = frappe.db.get_value("Item",
 				item.item_code, ["website_warehouse", "is_stock_item"])