[REF] pos_restaurant: adapt code after jQuery update

Part of task 1896658

Co-authored-by: Aaron Bohy <aab@odoo.com>
Co-authored-by: Christophe Matthieu <chm@odoo.com>
Co-authored-by: Mathieu Duckerts-Antoine <dam@odoo.com>
Co-authored-by: David Monjoie <dmo@odoo.com>
Co-authored-by: Martin Geubelle <mge@odoo.com>
Co-authored-by: svs-odoo <svs@odoo.com>
Co-authored-by: Vincent Schippefilt <vsc@odoo.com>

addons/pos_restaurant/static/src/js/floors.js

@@ -421,7 +421,7 @@ var FloorScreenWidget = screens.ScreenWidget.extend({
                 method: 'write',
                 args: [[this.floor.id], {'background_color': background}],
             })
-            .fail(function (type, err){
+            .guardedCatch(function (){
                 self.gui.show_popup('error',{
                     'title':_t('Changes could not be saved'),
                     'body': _t('You must be connected to the internet to save your changes.'),