Upgrade to XStream 1.4.18.

Closes #2152

pom.xml

@@ -20,7 +20,7 @@
 		<awaitility>4.0.2</awaitility>
 		<jta>1.1</jta>
 		<beanutils>1.9.2</beanutils>
-		<xstream>1.4.17</xstream>
+		<xstream>1.4.18</xstream>
 		<pool>2.9.0</pool>
 		<lettuce>6.1.4.RELEASE</lettuce>
 		<jedis>3.6.3</jedis>

src/test/java/org/springframework/data/redis/test/XstreamOxmSerializerSingleton.java

@@ -18,6 +18,8 @@ package org.springframework.data.redis.test;
 import org.springframework.data.redis.serializer.OxmSerializer;
 import org.springframework.oxm.xstream.XStreamMarshaller;
 
+import com.thoughtworks.xstream.security.AnyTypePermission;
+
 /**
  * @author Mark Paluch
  */
@@ -31,6 +33,7 @@ public final class XstreamOxmSerializerSingleton {
 
 		// XStream serializer
 		XStreamMarshaller xstream = new XStreamMarshaller();
+		xstream.getXStream().addPermission(AnyTypePermission.ANY);
 		try {
 			xstream.afterPropertiesSet();
 		} catch (Exception ex) {