Update log4j.version to v2.23.1

Author: renovate[bot]

pom.xml

@@ -17,7 +17,7 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <slf4j.version>1.7.12</slf4j.version>
-        <log4j.version>2.2</log4j.version>
+        <log4j.version>2.23.1</log4j.version>
         <junit.version>4.12</junit.version>
     </properties>