python 2-3 fix, *.keys() return dict_keys object in py3 (#15409)

diff --git a/erpnext/manufacturing/doctype/bom/bom.py b/erpnext/manufacturing/doctype/bom/bom.py
index 5e9f46c..7ad5a7f 100644
--- a/erpnext/manufacturing/doctype/bom/bom.py
+++ b/erpnext/manufacturing/doctype/bom/bom.py
@@ -701,7 +701,7 @@
 		items.setdefault(d.item_code, d.rate)
 
 	non_stock_items = frappe.get_all('Item',
-		fields="name", filters={'name': ('in', items.keys()), 'ifnull(is_stock_item, 0)': 0}, as_list=1)
+		fields="name", filters={'name': ('in', list(items.keys())), 'ifnull(is_stock_item, 0)': 0}, as_list=1)
 
 	for name in non_stock_items:
 		stock_entry.append('additional_costs', {