Upgrade to Maven Wrapper 3.9.6.

See #2803

Author: mp911de

.mvn/wrapper/maven-wrapper.properties

@@ -1,2 +1,2 @@
-#Wed Oct 04 16:58:12 PDT 2023
-distributionUrl=https\://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.5/apache-maven-3.9.5-bin.zip
+#Thu Dec 14 08:34:14 CET 2023
+distributionUrl=https\://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.6/apache-maven-3.9.6-bin.zip