[FIX] delivery: return label portal download

Before this commit
================
- Portal users were not able to download the return label via the portal because
the Access token is not passed.

After this commit
================
- Portal users are able to download return labels via the portal.

task-3245766

closes odoo/odoo#147315

X-original-commit: 2b9fe4854078e237b5da7e97e4ff3fa8d6c270a9
Signed-off-by: William Henrotin (whe) <whe@odoo.com>

addons/stock_delivery/models/delivery_carrier.py

@@ -50,9 +50,12 @@ class DeliveryCarrier(models.Model):
     def get_return_label(self, pickings, tracking_number=None, origin_date=None):
         self.ensure_one()
         if self.can_generate_return:
-            return getattr(self, '%s_get_return_label' % self.delivery_type)(
+            res = getattr(self, '%s_get_return_label' % self.delivery_type)(
                 pickings, tracking_number, origin_date
             )
+            if self.get_return_label_from_portal:
+                pickings.return_label_ids.generate_access_token()
+            return res
 
     def get_return_label_prefix(self):
         return 'LabelReturn-%s' % self.delivery_type

addons/stock_delivery/views/delivery_portal_template.xml

@@ -25,7 +25,7 @@
                 </t>
             </div>
             <div t-if="picking.carrier_id.get_return_label_from_portal and picking.return_label_ids">
-                <a class="ms-3" t-attf-href="/web/content/#{picking.return_label_ids[:1].id}" target="_blank">
+                <a class="ms-3" t-attf-href="/web/content/#{picking.return_label_ids[:1].id}?access_token=#{i.return_label_ids[:1].access_token}" target="_blank">
                     Print Return Label
                 </a>
             </div>