UI: upgrade Ember to 5.4 (#26708)

ui/lib/ldap/addon/components/page/overview.hbs

@@ -51,6 +51,7 @@
         <div class="has-top-margin-m is-flex">
           <SearchSelect
             class="is-flex-1"
+            @ariaLabel="Role"
             @placeholder="Select a role"
             @disallowNewItems={{true}}
             @options={{@roles}}

ui/lib/ldap/index.js

@@ -16,6 +16,10 @@ module.exports = buildEngine({
     enabled: false,
   }),
 
+  babel: {
+    plugins: [require.resolve('ember-concurrency/async-arrow-task-transform')],
+  },
+
   isDevelopingAddon() {
     return true;
   },