Bump xstream from 1.3 to 1.4.6 in /gshell-support/gshell-marshal

Bumps xstream from 1.3 to 1.4.6.

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/gshell-support/gshell-marshal/pom.xml b/gshell-support/gshell-marshal/pom.xml
index ce501fa..cdb70dc 100644
--- a/gshell-support/gshell-marshal/pom.xml
+++ b/gshell-support/gshell-marshal/pom.xml
@@ -52,7 +52,7 @@
         <dependency>
             <groupId>com.thoughtworks.xstream</groupId>
             <artifactId>xstream</artifactId>
-            <version>1.3</version>
+            <version>1.4.6</version>
         </dependency>
     </dependencies>