[FIX] payment_sips: allow to override the default atos url.

Sips is generic, and others services that Atos use the same protocol.
It is not user-friendly, but that allow user to use alternative service
like 'Sogenactif'.

In next version, we need to add field on config to specify it and the
InterfaceVersion that can differ according to the provider.

addons/payment_sips/models/payment.py

@@ -48,7 +48,8 @@ class AcquirerSips(models.Model):
             'prod': 'https://payment-webinit.sips-atos.com/paymentInit',
             'test': 'https://payment-webinit.simu.sips-atos.com/paymentInit', }
 
-        return {'sips_form_url': url.get(environment, url['test']), }
+        icp_value = self.env['ir.config_parameter'].sudo().get_param('acquirer_sips_url_%s' % environment)
+        return {'sips_form_url': icp_value or url.get(environment, url['test']), }
 
     def _sips_generate_shasign(self, values):
         """ Generate the shasign for incoming or outgoing communications.