Update tests due to deprecations in Reactor

spring-web/src/test/java/org/springframework/web/filter/reactive/ServerWebExchangeContextFilterTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.springframework.web.filter.reactive;
 
 import java.time.Duration;
@@ -33,10 +34,10 @@ import static org.assertj.core.api.Assertions.assertThat;
  * Unit tests for {@link ServerWebExchangeContextFilter}.
  * @author Rossen Stoyanchev
  */
-public class ServerWebExchangeContextFilterTests {
+class ServerWebExchangeContextFilterTests {
 
 	@Test
-	public void extractServerWebExchangeFromContext() {
+	void extractServerWebExchangeFromContext() {
 		MyService service = new MyService();
 
 		HttpHandler httpHandler = WebHttpHandlerBuilder
@@ -61,7 +62,7 @@ public class ServerWebExchangeContextFilterTests {
 		}
 
 		public Mono<String> service() {
-			return Mono.just("result").subscriberContext(context -> {
+			return Mono.just("result").contextWrite(context -> {
 				ServerWebExchangeContextFilter.get(context).ifPresent(exchangeRef::set);
 				return context;
 			});