Not allow create payments when payment_amount is 0 (zero)
Scenario:
- Financial / Payments / Lines to Pay
- Select a record and change to form view.
- Copy/paste url in new browser tab.
Steps:
- click first tab and do "Lines to pay" wizard: Create a payment with that amount is from line.
- click second tab and do "Lines to pay" wizard: Create a payment with that amount is 0.