chore: force reload doctype before running patch

fixes Unknown column 'against_blanket_order' in 'field list'

Signed-off-by: Chinmay D. Pai <chinmaydpai@gmail.com>
diff --git a/erpnext/patches/v12_0/set_against_blanket_order_in_sales_and_purchase_order.py b/erpnext/patches/v12_0/set_against_blanket_order_in_sales_and_purchase_order.py
index 3fccbfa..85202bf 100644
--- a/erpnext/patches/v12_0/set_against_blanket_order_in_sales_and_purchase_order.py
+++ b/erpnext/patches/v12_0/set_against_blanket_order_in_sales_and_purchase_order.py
@@ -1,10 +1,11 @@
 import frappe
+
 def execute():
 
-	frappe.reload_doc('selling', 'doctype', frappe.scrub('Sales Order Item'))
-	frappe.reload_doc('buying', 'doctype', frappe.scrub('Purchase Order Item'))
+	frappe.reload_doc('selling', 'doctype', 'sales_order_item', force=True)
+	frappe.reload_doc('buying', 'doctype', 'purchase_order_item', force=True)
 
-	for doctype in ['Sales Order Item', 'Purchase Order Item']:
+	for doctype in ('Sales Order Item', 'Purchase Order Item'):
 		frappe.db.sql("""
 			UPDATE `tab{0}`
 			SET against_blanket_order = 1