Tokens with no expiration date

According to the field definition, PaymentMethod entities do support tokens/payment methods that don't expire:

    $fields['expires'] = BaseFieldDefinition::create('timestamp')
      ->setLabel(t('Expires'))
      ->setDescription(t('The time when the payment method expires. 0 for never.'))
..

I see that \Drupal\commerce_wallee\Services\PaymentSdk::createPaymentMethod checks if the expiration date is a valid date and only converts it then. Maybe it should use 0 as the default value and not null, but it's unlikely that commerce does a type safe check here.

So without further checking, I'd say that should work.

@berdir thank you for your comment! We change it like in the patch bellow. So we try to change both the createPaymentMethod and webhookTokenVersion. If you think is working like this, we can publish it. Thank you for your quick review.