### CI Link

https://gradle-enterprise.elastic.co/s/ozb6lycxc43es/console-log?task=:security-authorization-engine:compileJava

### Repro line

cd plugin/examples; ./gradlew build --include-build ../..

### Does it reproduce?

Yes

### Applicable branches

master

### Failure history

_No response_

### Failure excerpt

After merging https://github.com/elastic/elasticsearch/pull/86246 example builds started failing with compilation errors 

```
> Task :security-authorization-engine:compileJava FAILED
/Users/rene/dev/elasticsearch-master/plugins/examples/security-authorization-engine/src/main/java/org/elasticsearch/example/CustomAuthorizationEngine.java:50: error: cannot find symbol
        if (authentication.getUser().isRunAs()) {
                                    ^
  symbol:   method isRunAs()
  location: class User
/Users/rene/dev/elasticsearch-master/plugins/examples/security-authorization-engine/src/main/java/org/elasticsearch/example/CustomAuthorizationEngine.java:52: error: cannot find symbol
                new CustomAuthorizationInfo(authentication.getUser().authenticatedUser().roles(), null);
                                                                    ^
  symbol:   method authenticatedUser()
  location: class User
/Users/rene/dev/elasticsearch-master/plugins/examples/security-authorization-engine/src/main/java/org/elasticsearch/example/CustomAuthorizationEngine.java:61: error: cannot find symbol
        if (isSuperuser(requestInfo.getAuthentication().getUser().authenticatedUser())) {
                                                                 ^
  symbol:   method authenticatedUser()
  location: class User
Note: /Users/rene/dev/elasticsearch-master/plugins/examples/security-authorization-engine/src/main/java/org/elasticsearch/example/CustomAuthorizationEngine.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
3 errors

```
plugins/examples/security-authorization-engine/src/main/java/org/elasticsearch/example/CustomAuthorizationEngine.java
/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0 and the Server Side Public License, v 1; you may not use this file except
 * in compliance with, at your election, the Elastic License 2.0 or the Server
 * Side Public License, v 1.
 */
package org.elasticsearch.example;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.cluster.metadata.IndexAbstraction;
import org.elasticsearch.xpack.core.security.action.user.GetUserPrivilegesRequest;