Bump com.thoughtworks.xstream:xstream from 1.4.20 to 1.4.21

Bumps [com.thoughtworks.xstream:xstream](https://github.com/x-stream/xstream) from 1.4.20 to 1.4.21.
- [Release notes](https://github.com/x-stream/xstream/releases)
- [Commits](https://github.com/x-stream/xstream/commits)

---
updated-dependencies:
- dependency-name: com.thoughtworks.xstream:xstream
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

pom.xml

@@ -152,7 +152,7 @@
     <jackson-bom.version>2.13.4.20221013</jackson-bom.version>
     <jsonpath.version>2.9.0</jsonpath.version>
     <jettison.version>1.5.4</jettison.version>
-    <xstream.core.version>1.4.20</xstream.core.version>
+    <xstream.core.version>1.4.21</xstream.core.version>
     <woodstox.version>6.4.0</woodstox.version>
     <snakeyaml.version>1.33</snakeyaml.version>