Add SpringHeaderCheck to enforce using "2012-present"

This commit also fixes copyright headers that don't follow it.

See gh-46527

Signed-off-by: Johnny Lim <izeye@naver.com>

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/web/graphql/runtimewiring/GreetingController.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/metrics/buffering/BufferedStartupStep.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/metrics/buffering/BufferingApplicationStartup.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/metrics/buffering/StartupTimeline.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/ConstructorBound.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2019-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/convert/PeriodStyle.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/convert/PeriodToStringConverter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-present the original author or authors.
+ * Copyright 2012-present 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.

src/checkstyle/checkstyle.xml

@@ -7,6 +7,9 @@
 		<property name="file" value="${config_loc}/checkstyle-suppressions.xml"/>
 	</module>
 	<module name="io.spring.javaformat.checkstyle.SpringChecks" />
+	<module name="io.spring.javaformat.checkstyle.check.SpringHeaderCheck">
+		<property name="headerCopyrightPattern" value="2012-present" />
+	</module>
 	<module name="com.puppycrawl.tools.checkstyle.TreeWalker">
 		<module name="io.spring.javaformat.checkstyle.check.SpringDeprecatedCheck" />
 		<module name="io.spring.javaformat.checkstyle.check.SpringJUnit5Check" />