Upgrade tests to TestNG 7.1

See gh-24298

spring-test/src/test/java/org/springframework/test/context/cache/ClassLevelDirtiesContextTestNGTests.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.
@@ -21,7 +21,6 @@ import java.util.concurrent.atomic.AtomicInteger;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
-import org.testng.ITestNGListener;
 import org.testng.TestNG;
 
 import org.springframework.beans.factory.annotation.Autowired;
@@ -140,7 +139,7 @@ class ClassLevelDirtiesContextTestNGTests {
 
 		final TrackingTestNGTestListener listener = new TrackingTestNGTestListener();
 		final TestNG testNG = new TestNG();
-		testNG.addListener((ITestNGListener) listener);
+		testNG.addListener(listener);
 		testNG.setTestClasses(new Class<?>[] { testClass });
 		testNG.setVerbose(0);
 		testNG.run();

spring-test/src/test/java/org/springframework/test/context/junit4/FailingBeforeAndAfterMethodsTestNGTests.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.
@@ -21,7 +21,6 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 import org.junit.runners.Parameterized.Parameters;
-import org.testng.ITestNGListener;
 import org.testng.TestNG;
 
 import org.springframework.test.context.ContextConfiguration;
@@ -97,7 +96,7 @@ public class FailingBeforeAndAfterMethodsTestNGTests {
 	public void runTestAndAssertCounters() throws Exception {
 		TrackingTestNGTestListener listener = new TrackingTestNGTestListener();
 		TestNG testNG = new TestNG();
-		testNG.addListener((ITestNGListener) listener);
+		testNG.addListener(listener);
 		testNG.setTestClasses(new Class<?>[] {this.clazz});
 		testNG.setVerbose(0);
 		testNG.run();