Drupal 10 compatibility

• /src/Plugin/Commerce/PaymentGateway/RedirectCheckout.php
• /paytr_payment.libraries.yml
• /js/paytr_payment.checkout.js
• /paytr_payment.info.yml

Closes #3467122

js/paytr_payment.checkout.js

-(function ($, Drupal, drupalSettings) {
+(function ($, Drupal, drupalSettings, once) {
   'use strict';
 
   Drupal.behaviors.offsiteForm = {
     attach: function (context) {
       let data = JSON.parse(drupalSettings.paytr_payment_iframe);
-      $($(context).find('#paytr-payment-checkout')).append('<iframe src="https://www.paytr.com/odeme/guvenli/'+data.token+'" id="paytriframe" frameBorder="0" scrolling="no" style="width: 100%;"></iframe><script>iFrameResize({},\'#paytriframe\');</script>');
+      once('offsiteForm', '#paytr-payment-checkout', context).forEach(function (element) {
+        $(element).append('<iframe src="https://www.paytr.com/odeme/guvenli/' + data.token + '" id="paytriframe" frameBorder="0" scrolling="no" style="width: 100%;"></iframe><script>iFrameResize({},\'#paytriframe\');</script>');
+      });
     }
   };
 
-}(jQuery, Drupal, drupalSettings));
+}(jQuery, Drupal, drupalSettings, once));