Bump org.apache.maven.plugins:maven-checkstyle-plugin (#135)

Bumps [org.apache.maven.plugins:maven-checkstyle-plugin](https://github.com/apache/maven-checkstyle-plugin) from 3.3.1 to 3.4.0.
- [Commits](apache/maven-checkstyle-plugin@maven-checkstyle-plugin-3.3.1...maven-checkstyle-plugin-3.4.0)

---
updated-dependencies:
- dependency-name: org.apache.maven.plugins:maven-checkstyle-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Bruno Verachten <[email protected]>

pom.xml

@@ -94,7 +94,7 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-checkstyle-plugin</artifactId>
-        <version>3.3.1</version>
+        <version>3.4.0</version>
 	<!-- enable this when the plugin requires Java 11 -->
 	<!--
         <dependencies>