Support jar:nested in SchemaFactoryUtils (#1401)

* Support jar:nested in SchemaFactoryUtils

Closes gh-1393

* Update SchemaFactoryUtils

Required nested not jar:nested

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Co-authored-by: Corneil du Plessis <corneil.duplessis@gmail.com>

Author: izeye

spring-xml/src/main/java/org/springframework/xml/validation/SchemaFactoryUtils.java

@@ -52,7 +52,7 @@ public static SchemaFactory newInstance(String schemaLanguage) {
 
 		try {
 			schemaFactory.setProperty(XMLConstants.ACCESS_EXTERNAL_SCHEMA,
-					ResourceUtils.URL_PROTOCOL_FILE + "," + "jar:file" + "," + ResourceUtils.URL_PROTOCOL_WSJAR);
+					ResourceUtils.URL_PROTOCOL_FILE + "," + "jar:file" + "," + "nested" + "," + ResourceUtils.URL_PROTOCOL_WSJAR);
 		} catch (SAXNotRecognizedException | SAXNotSupportedException e) {
 			if (log.isWarnEnabled()) {
 				log.warn(XMLConstants.ACCESS_EXTERNAL_SCHEMA + " property not supported by "