Build(deps): Bump log4j2.version from 2.20.0 to 2.21.0

Bumps `log4j2.version` from 2.20.0 to 2.21.0.

Updates `org.apache.logging.log4j:log4j-api` from 2.20.0 to 2.21.0

Updates `org.apache.logging.log4j:log4j-core` from 2.20.0 to 2.21.0

Updates `org.apache.logging.log4j:log4j-slf4j-impl` from 2.20.0 to 2.21.0

---
updated-dependencies:
- dependency-name: org.apache.logging.log4j:log4j-api
  dependency-type: direct:production
  update-type: version-update:semver-minor
- 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
...

Signed-off-by: dependabot[bot] <support@github.com>

pom.xml

@@ -355,7 +355,7 @@
 
   <properties>
     <slf4j.version>1.7.36</slf4j.version>
-    <log4j2.version>2.20.0</log4j2.version>
+    <log4j2.version>2.21.0</log4j2.version>
     <spring.version>5.3.30</spring.version>
     <junit5.version>5.10.0</junit5.version>
     <jetty.version>11.0.17</jetty.version>