Start building against Spring Security 6.4.0 snapshots

See gh-42568

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/oauth2/server/servlet/OAuth2AuthorizationServerAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -33,7 +33,7 @@ import org.springframework.security.oauth2.server.authorization.OAuth2Authorizat
  * <p>
  * <strong>Note:</strong> This configuration and
  * {@link OAuth2AuthorizationServerJwtAutoConfiguration} work together to ensure that the
- * {@link org.springframework.security.config.annotation.ObjectPostProcessor} is defined
+ * {@link org.springframework.security.config.ObjectPostProcessor} is defined
  * <strong>BEFORE</strong> {@link UserDetailsServiceAutoConfiguration} so that a
  * {@link org.springframework.security.core.userdetails.UserDetailsService} can be created
  * if necessary.

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/servlet/UserDetailsServiceAutoConfiguration.java

@@ -38,7 +38,7 @@ import org.springframework.context.annotation.Conditional;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.AuthenticationManagerResolver;
 import org.springframework.security.authentication.AuthenticationProvider;
-import org.springframework.security.config.annotation.ObjectPostProcessor;
+import org.springframework.security.config.ObjectPostProcessor;
 import org.springframework.security.core.userdetails.User;
 import org.springframework.security.core.userdetails.UserDetailsService;
 import org.springframework.security.crypto.password.PasswordEncoder;

spring-boot-project/spring-boot-dependencies/build.gradle

@@ -2114,7 +2114,7 @@ bom {
 			releaseNotes("https://github.com/spring-projects/spring-retry/releases/tag/v{version}")
 		}
 	}
-	library("Spring Security", "6.4.0-M4") {
+	library("Spring Security", "6.4.0-SNAPSHOT") {
 		considerSnapshots()
 		group("org.springframework.security") {
 			imports = [