Remove @Configuration meta-annotation from @Enable*Session annotations

Closes gh-1361

spring-session-docs/modules/ROOT/examples/java/docs/SpringWebSessionConfig.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2019 the original author or authors.
+ * Copyright 2014-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,11 +19,13 @@ package docs;
 import java.util.concurrent.ConcurrentHashMap;
 
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
 import org.springframework.session.ReactiveMapSessionRepository;
 import org.springframework.session.ReactiveSessionRepository;
 import org.springframework.session.config.annotation.web.server.EnableSpringWebSession;
 
 // tag::class[]
+@Configuration(proxyBeanMethods = false)
 @EnableSpringWebSession
 public class SpringWebSessionConfig {