Bump checkstyle from 9.0 to 9.1

Bumps [checkstyle](https://github.com/checkstyle/checkstyle) from 9.0 to 9.1.
- [Release notes](https://github.com/checkstyle/checkstyle/releases)
- [Commits](checkstyle/checkstyle@checkstyle-9.0...checkstyle-9.1)

---
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>

pom.xml

@@ -356,7 +356,7 @@ limitations under the License.
             <dependency>
               <groupId>com.puppycrawl.tools</groupId>
               <artifactId>checkstyle</artifactId>
-              <version>9.0</version>
+              <version>9.1</version>
             </dependency>
             <!-- MCHECKSTYLE-327: the maven_checks.xml was moved to a shared project -->
             <dependency>