Fix Checkstyle for CsrfWebFilter

Issue gh-9337

Author: rwinch

web/src/main/java/org/springframework/security/web/server/csrf/CsrfWebFilter.java

@@ -131,8 +131,8 @@ public static void skipExchange(ServerWebExchange exchange) {
 
 	private Mono<Void> validateToken(ServerWebExchange exchange) {
 		return this.csrfTokenRepository.loadToken(exchange)
-				.switchIfEmpty(Mono
-						.defer(() -> Mono.error(new CsrfException("An expected CSRF token cannot be found"))))
+				.switchIfEmpty(
+						Mono.defer(() -> Mono.error(new CsrfException("An expected CSRF token cannot be found"))))
 				.filterWhen((expected) -> containsValidCsrfToken(exchange, expected))
 				.switchIfEmpty(Mono.defer(() -> Mono.error(new CsrfException("Invalid CSRF Token")))).then();
 	}

web/src/test/java/org/springframework/security/web/server/csrf/CsrfWebFilterTests.java

@@ -34,7 +34,6 @@
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.reactive.function.BodyInserters;
-import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebFilterChain;
 import org.springframework.web.server.WebSession;
 
@@ -92,7 +91,7 @@ public void filterWhenPostAndEstablishedCsrfTokenAndRequestMissingTokenThenCsrfE
 		StepVerifier.create(result).verifyComplete();
 		assertThat(this.post.getResponse().getStatusCode()).isEqualTo(HttpStatus.FORBIDDEN);
 		StepVerifier.create(this.post.getResponse().getBodyAsString())
-				.assertNext(b -> assertThat(b).contains("An expected CSRF token cannot be found"));
+				.assertNext((body) -> assertThat(body).contains("An expected CSRF token cannot be found"));
 	}
 
 	@Test