Apply suggestion from @deboragracio

Co-authored-by: deboragracio <63159404+deboragracio@users.noreply.github.com>

Author: MaximilianFT

HOWTO_01_Payment_csharp/README.MD

@@ -36,7 +36,7 @@ In many payment vendor apps, it is possible to add a tip to the payment amount.
 4. The payment app opens, and the waiter hands the mobile device to the guest.
 5. The guest sees a TIP entry screen and adds a tip of 2€.
 6. The guest now pays the full sum of 12€.
-- The payment app reports a paid amount of 12€ (including 2€ of tip)
+7. The payment app reports a paid amount of 12€ (including 2€ tip).
 - The fiskaltrust InStore App / POS System API does report back the following in the payment response (see also example in the POS System API docs):
   - 2 pay items
   - Pay item 1: The fully paid amount with the receipt -> 12€