Use status instead of statusText (#3515)

As of HTTP/2 the field statusText can be empty ( See: jquery/api.jquery.com@be6de73 ). Thus the field statusText is no longer relyable to base logic on. The field status of the XMLHttpRequest remains intact, so we can base the logic on that field.

Author: fuegas

src/rails_admin/remote-form.js

@@ -105,9 +105,8 @@ import * as bootstrap from "bootstrap/dist/js/bootstrap.esm";
       document.dispatchEvent(event);
 
       form.bind("ajax:complete", function (event) {
-        var data = event.detail[0],
-          status = event.detail[1];
-        if (status == "OK") {
+        var data = event.detail[0];
+        if (data.status == 200) {
           var json = $.parseJSON(data.responseText);
           var option =
             '<option value="' +