Test servlet 3.1 compatibility in deployment tests

Closes gh-28906

spring-boot-tests/spring-boot-deployment-tests/build.gradle

@@ -13,10 +13,11 @@ configurations {
 }
 
 dependencies {
+	implementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-actuator"))
+	implementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-security"))
 	implementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-web")) {
 		exclude group: "org.hibernate.validator"
 	}
-	implementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-actuator"))
 
 	intTestImplementation(enforcedPlatform(project(path: ":spring-boot-project:spring-boot-parent")))
 	intTestImplementation(project(":spring-boot-project:spring-boot-starters:spring-boot-starter-test"))

spring-boot-tests/spring-boot-deployment-tests/src/intTest/java/sample/AbstractDeploymentIntegrationTests.java

@@ -95,6 +95,7 @@ abstract class AbstractDeploymentIntegrationTests {
 			TestRestTemplate rest = new TestRestTemplate(new RestTemplateBuilder()
 					.rootUri("http://" + this.container.getHost() + ":" + this.container.getMappedPort(this.port)
 							+ "/spring-boot")
+					.basicAuthentication("test", "test")
 					.requestFactory(() -> new HttpComponentsClientHttpRequestFactory(HttpClients.custom()
 							.setRetryHandler(new StandardHttpRequestRetryHandler(10, false)).build())));
 			try {

spring-boot-tests/spring-boot-deployment-tests/src/intTest/java/sample/Tomcat85DeploymentIntegrationTests.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2012-2021 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package sample;
+
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+/**
+ * Deployment integration tests for Tomcat 8.5 (a Servlet 3.1 container).
+ *
+ * @author Andy Wilkinson
+ */
+@Testcontainers(disabledWithoutDocker = true)
+class Tomcat85DeploymentIntegrationTests extends AbstractDeploymentIntegrationTests {
+
+	@Container
+	static WarDeploymentContainer container = new WarDeploymentContainer("tomcat:8.5.73-jdk8-openjdk",
+			"/usr/local/tomcat/webapps", DEFAULT_PORT);
+
+	@Override
+	WarDeploymentContainer getContainer() {
+		return container;
+	}
+
+}

spring-boot-tests/spring-boot-deployment-tests/src/main/resources/application.yml

@@ -1 +1,6 @@
+spring:
+  security:
+    user:
+      name: test
+      password: test
 management.endpoints.web.exposure.include: '*'