[IMP] website_sale_digital: add message when no record
[IMP] website_sale_digital: add message when no record

Proper message should be displayed when no records in
attachments kanban view when we click on 'File' stat
button on product form view.

dfang/odoo,ygol/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo,ygol/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,dfang/odoo,dfang/odoo,dfang/odoo,ygol/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo