[Feat] Payment Request enhancements
No payment link generation if no payment gateways are selected
Currently payment gateways are mandatory in Payment Requests, unless the checkbox "No payment link" is selected. We should also allow the creation of a payment request without payment link if no payment gateways are added to the document.
Allow fictional payment gateways
Currently it is not possible to create a payment gateway for a bank account in order to display a page with SEPA payment information
Move the payment gateway template determination at the customer level + customer group + company level (like account determination)
Add a condition in payment gateways to automatically exclude some gateways based on the payment amount.
Eg. Propose a Stripe payment for all payment < 500 €, but GoCardless for all amounts