Add javax.xml.namespace.QName to trusted classes in Jackson serializer

This class is safe to deserialize according to Jackson:
https://github.com/FasterXML/jackson-databind/blob/master/src/main/java/com/fasterxml/jackson/databind/jsontype/impl/SubTypeValidator.java

This also has been checked against Jackson 2.11 to confirm
the backport of this enhancement to 4.3.x.

Resolves #4044

Author: fmbenhassine

spring-batch-core/src/main/java/org/springframework/batch/core/repository/dao/Jackson2ExecutionContextStringSerializer.java

@@ -254,6 +254,7 @@ protected TypeIdResolver idResolver(MapperConfig<?> config,
      */
     static class TrustedTypeIdResolver implements TypeIdResolver {
         private static final Set<String> TRUSTED_CLASS_NAMES = Collections.unmodifiableSet(new HashSet(Arrays.asList(
+                "javax.xml.namespace.QName",
                 "java.util.UUID",
                 "java.util.ArrayList",
                 "java.util.Arrays$ArrayList",