Bump xstream from 1.3 to 1.4.6

Bumps xstream from 1.3 to 1.4.6.

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index 31f8796..c3e6fcd 100644
--- a/pom.xml
+++ b/pom.xml
@@ -664,7 +664,7 @@
             <dependency>
                 <groupId>com.thoughtworks.xstream</groupId>
                 <artifactId>xstream</artifactId>
-                <version>1.3</version>
+                <version>1.4.6</version>
                 <exclusions>
                     <exclusion>
                     <!-- xom is an optional dependency of xstream. Its also