update modified date to reload doc (#15385)

diff --git a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.json b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.json
index 6c0ee8b..504d45f 100755
--- a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.json
+++ b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.json
@@ -4593,7 +4593,7 @@
  "istable": 0, 
  "max_attachments": 0, 
  "menu_index": 0, 
- "modified": "2018-08-21 14:44:31.220376", 
+ "modified": "2018-09-11 14:44:31.220376", 
  "modified_by": "Administrator", 
  "module": "Accounts", 
  "name": "Purchase Invoice",