Fail build on missing configuration property descriptions

Closes gh-31916

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/server/Encoding.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2020 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.
@@ -60,7 +60,7 @@ public class Encoding {
 	private Boolean forceResponse;
 
 	/**
-	 * Locale in which to encode mapping.
+	 * Mapping of locale to charset for response encoding..
 	 */
 	private Map<Locale, Charset> mapping;
 

spring-boot-project/spring-boot/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -324,6 +324,7 @@
     {
       "name": "spring.jpa.defer-datasource-initialization",
       "type": "java.lang.Boolean",
+      "description": "Whether to defer DataSource initialization until after any EntityManagerFactory beans have been created and initialized.",
       "defaultValue": false
     },
     {