fix: xmppserver/pom.xml to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-COMMONSIO-8161190

Author: snyk-bot

xmppserver/pom.xml

@@ -423,7 +423,7 @@
         <dependency>
             <groupId>commons-fileupload</groupId>
             <artifactId>commons-fileupload</artifactId>
-            <version>1.5</version>
+            <version>1.6.0</version>
         </dependency>
         <dependency>
             <groupId>org.directwebremoting</groupId>