Update copyright year of change file

See gh-30329

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/features/developingwebapplications/springmvc/json/MyJsonComponent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2022 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.