Bump org.mockito:mockito-core from 5.20.0 to 5.21.0 in /lang/java

Bumps [org.mockito:mockito-core](https://github.com/mockito/mockito) from 5.20.0 to 5.21.0.
- [Release notes](https://github.com/mockito/mockito/releases)
- [Commits](mockito/mockito@v5.20.0...v5.21.0)

---
updated-dependencies:
- dependency-name: org.mockito:mockito-core
  dependency-version: 5.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

lang/java/pom.xml

@@ -50,7 +50,7 @@
     <jopt-simple.version>5.0.4</jopt-simple.version>
     <junit5.version>5.14.1</junit5.version>
     <maven-core.version>3.9.6</maven-core.version>
-    <mockito.version>5.20.0</mockito.version>
+    <mockito.version>5.21.0</mockito.version>
     <netty.version>4.2.9.Final</netty.version>
     <protobuf.version>4.33.2</protobuf.version>
     <reload4j.version>1.2.26</reload4j.version>