Bump com.puppycrawl.tools:checkstyle in /vividus-studio-server

Bumps [com.puppycrawl.tools:checkstyle](https://github.com/checkstyle/checkstyle) from 10.20.2 to 10.21.0.
- [Release notes](https://github.com/checkstyle/checkstyle/releases)
- [Commits](checkstyle/checkstyle@checkstyle-10.20.2...checkstyle-10.21.0)

---
updated-dependencies:
- dependency-name: com.puppycrawl.tools:checkstyle
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

vividus-studio-server/vividus-studio-plugin/pom.xml

@@ -16,7 +16,7 @@
         <maven.compiler.target>21</maven.compiler.target>
         <org.mockito.version>5.14.2</org.mockito.version>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <checkstyle.version>10.20.2</checkstyle.version>
+        <checkstyle.version>10.21.0</checkstyle.version>
         <checkstyle.plugin.version>3.6.0</checkstyle.plugin.version>
         <sevntu.checkstyle.plugin.version>1.44.1</sevntu.checkstyle.plugin.version>
         <hamcrest.version>3.0</hamcrest.version>