Revert workaround for Java 8 compiler bug

Author: sbrannen

spring-test/src/main/java/org/springframework/test/context/TestContext.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2022 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.
@@ -43,8 +43,6 @@
  * @see TestContextManager
  * @see TestExecutionListener
  */
-// Suppression required due to bug in javac in Java 8: presence of default method in a Serializable interface
-@SuppressWarnings("serial")
 public interface TestContext extends AttributeAccessor, Serializable {
 
 	/**