[FIX] pos_restaurant: Allow more complex URL schemes for printers

For example: https://abc.def:8080
It is already allowed for the printer in main point_of_sale module.
Apply the same schemes in pos_restaurant.

Closes #13769

addons/pos_restaurant/static/src/js/multiprint.js

@@ -54,7 +54,14 @@ models.load_models({
 
         for(var i = 0; i < printers.length; i++){
             if(active_printers[printers[i].id]){
-                var printer = new Printer(self,{url:'http://'+printers[i].proxy_ip+':8069'});
+                var url = printers[i].proxy_ip;
+                if(url.indexOf('//') < 0){
+                    url = 'http://'+url;
+                }
+                if(url.indexOf(':',url.indexOf('//')+2) < 0){
+                    url = url+':8069';
+                }
+                var printer = new Printer(self,{url:url});
                 printer.config = printers[i];
                 self.printers.push(printer);