[FIX] l10n_fr_pos_cert: allow you to remove reward line in FR PoS

Current behavior:
When a reward line had 0 quantity, it was considered as active and the
points were deducted from the customer's balance.

Steps to reproduce:
- Install l10n_fr_pos_cert
- Change the Current company to FR company
- Create a loyalty card program
- Open the POS and add a product to the order to get points and trigger
  the reward.
- Remove the reward line, it should go to 0 quantity instead of being
  removed.
- The point are still removed from the customer's balance.

opw-3372998

closes odoo/odoo#132573

X-original-commit: f170bebb38fff044a9f0e247095adc3aaf5a5074
Signed-off-by: Joseph Caburnay (jcb) <jcb@odoo.com>
Signed-off-by: Robin Engels (roen) <roen@odoo.com>

addons/l10n_fr_pos_cert/static/src/js/pos.js

@@ -20,6 +20,12 @@ patch(PosStore.prototype, {
     },
     disallowLineQuantityChange() {
         const result = super.disallowLineQuantityChange(...arguments);
+        let selectedOrderLine = this.selectedOrder.get_selected_orderline();
+        //Note: is_reward_line is a field in the pos_loyalty module
+        if (selectedOrderLine.is_reward_line) {
+            //Always allow quantity change for reward lines
+            return false || result;
+        }
         return this.is_french_country() || result;
     },
 });