Update DeferHttpSession Tests

Closes gh-11764

Author: rwinch

config/src/test/java/org/springframework/security/config/annotation/web/configuration/DeferHttpSessionJavaConfigTests.java

@@ -89,7 +89,6 @@ DefaultSecurityFilterChain springSecurity(HttpSecurity http) throws Exception {
 					.requireExplicitAuthenticationStrategy(true)
 				)
 				.csrf((csrf) -> csrf
-					.csrfRequestAttributeName("_csrf")
 					.csrfTokenRepository(csrfRepository)
 				);
 			// @formatter:on

config/src/test/resources/org/springframework/security/config/http/DeferHttpSessionTests-Explicit.xml

@@ -29,8 +29,7 @@
 	<http auto-config="true"
 			use-authorization-manager="true">
 		<intercept-url  pattern="/**" access="permitAll"/>
-		<csrf request-attribute-name="_csrf"
-			token-repository-ref="csrfRepository"/>
+		<csrf token-repository-ref="csrfRepository"/>
 		<request-cache ref="requestCache"/>
 		<session-management authentication-strategy-explicit-invocation="true"/>
 	</http>