Fix Java comment in Reference Manual

src/docs/asciidoc/core/core-beans.adoc

@@ -7366,7 +7366,7 @@ the abstract `createCommand()` method is overridden in such a way that it looks
 	@Bean
 	public CommandManager commandManager() {
 		// return new anonymous implementation of CommandManager with createCommand()
-		   overridden to return a new prototype Command object
+		// overridden to return a new prototype Command object
 		return new CommandManager() {
 			protected Command createCommand() {
 				return asyncCommand();