[FIX] point_of_sale: vat letter missing

When the pr of the skip receipt was merged, the vat letter feature was missing.

This commit put it back to the point of sale module so we can inherit it again in other modules.

Signed-off-by: rhe-odoo <rhe@odoo.com>

m

Part-of: odoo/odoo#133654

addons/point_of_sale/static/src/app/screens/receipt_screen/receipt_screen.js

@@ -169,6 +169,9 @@ export class ReceiptScreen extends Component {
             ticketImage,
         ]);
     }
+    getTaxLetter(taxes) {
+        return "";
+    }
 }
 
 registry.category("pos_screens").add("ReceiptScreen", ReceiptScreen);