Upgrade to Checkstyle 9.0 and spring-javaformat 0.0.29

This commit upgrades the Gradle build to use Checkstyle 9.0 and
spring-javaformat 0.0.29 (which internally uses Checkstyle 8.45.1).

Closes gh-27520

spring-context/src/main/java/org/springframework/context/support/PropertySourcesPlaceholderConfigurer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -185,9 +185,9 @@ public class PropertySourcesPlaceholderConfigurer extends PlaceholderConfigurerS
 	/**
 	 * Implemented for compatibility with
 	 * {@link org.springframework.beans.factory.config.PlaceholderConfigurerSupport}.
+	 * @throws UnsupportedOperationException in this implementation
 	 * @deprecated in favor of
 	 * {@link #processProperties(ConfigurableListableBeanFactory, ConfigurablePropertyResolver)}
-	 * @throws UnsupportedOperationException in this implementation
 	 */
 	@Override
 	@Deprecated

spring-context/src/main/java/org/springframework/jndi/JndiCallback.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2021 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.
@@ -44,8 +44,8 @@ public interface JndiCallback<T> {
 	 * <p>Implementations don't need to worry about error handling
 	 * or cleanup, as the JndiTemplate class will handle this.
 	 * @param ctx the current JNDI context
-	 * @throws NamingException if thrown by JNDI methods
 	 * @return a result object, or {@code null}
+	 * @throws NamingException if thrown by JNDI methods
 	 */
 	@Nullable
 	T doInContext(Context ctx) throws NamingException;