Bump log4j.version from 2.20.0 to 2.23.1

Bumps `log4j.version` from 2.20.0 to 2.23.1.

Updates `org.apache.logging.log4j:log4j-core` from 2.20.0 to 2.23.1

Updates `org.apache.logging.log4j:log4j-slf4j-impl` from 2.20.0 to 2.23.1

Updates `org.apache.logging.log4j:log4j-jul` from 2.20.0 to 2.23.1

---
updated-dependencies:
- dependency-name: org.apache.logging.log4j:log4j-core
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.apache.logging.log4j:log4j-slf4j-impl
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.apache.logging.log4j:log4j-jul
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pom.xml

@@ -79,7 +79,7 @@
         <packageVersion.dir>com/staffbase/plugins/sdk</packageVersion.dir>
         <packageVersion.package>${project.groupId}.json</packageVersion.package>
         <jose4j.version>0.9.4</jose4j.version>
-        <log4j.version>2.20.0</log4j.version>
+        <log4j.version>2.23.1</log4j.version>
         <junit.version>4.13.2</junit.version>
         <mockito.version>4.11.0</mockito.version>
     </properties>