Bump checkstyle from 8.42 to 9.1

Bumps [checkstyle](https://github.com/checkstyle/checkstyle) from 8.42 to 9.1.
- [Release notes](https://github.com/checkstyle/checkstyle/releases)
- [Commits](checkstyle/checkstyle@checkstyle-8.42...checkstyle-9.1)

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

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

pom.xml

@@ -244,7 +244,7 @@
     <project.build.outputTimestamp>2021-11-25T23:39:17Z</project.build.outputTimestamp>
     <scmpublish.content>${project.reporting.outputDirectory}</scmpublish.content><!-- mono-module doesn't require site:stage for scm-publish -->
     <junit5.version>5.8.1</junit5.version>
-    <checkstyle.version>8.42</checkstyle.version>
+    <checkstyle.version>9.1</checkstyle.version>
   </properties>
 
   <repositories>