FIX: allows to use icon-picker in wizard (#13786)

- inlines dasherize helper in sk
- uses an ajax helper to load wizard's ajax lib when in wizard
- amends wizard's ajax lib to work with string as first arg
- disabled loading spinner in wizard as it's not available

app/assets/javascripts/wizard/lib/ajax.js

@@ -14,11 +14,20 @@ export function getToken() {
 }
 
 export function ajax(args) {
+  let url;
+
+  if (arguments.length === 2) {
+    url = arguments[0];
+    args = arguments[1];
+  } else {
+    url = args.url;
+  }
+
   return new Promise((resolve, reject) => {
     args.headers = { "X-CSRF-Token": getToken() };
     args.success = (data) => run(null, resolve, data);
     args.error = (xhr) => run(null, reject, xhr);
-    args.url = getUrl(args.url);
+    args.url = getUrl(url);
     jQuery.ajax(args);
   });
 }