Bump com.puppycrawl.tools:checkstyle in the build-dependencies group

Bumps the build-dependencies group with 1 update: [com.puppycrawl.tools:checkstyle](https://github.com/checkstyle/checkstyle).


Updates `com.puppycrawl.tools:checkstyle` from 10.21.0 to 10.21.1
- [Release notes](https://github.com/checkstyle/checkstyle/releases)
- [Commits](checkstyle/checkstyle@checkstyle-10.21.0...checkstyle-10.21.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

pom.xml

@@ -219,7 +219,7 @@
             overridden by a CI job of the Checkstyle project so that they can
             check for regressions. Which is obviously good for us, too.
          -->
-        <puppycrawl.checkstyle.version>10.21.0</puppycrawl.checkstyle.version>
+        <puppycrawl.checkstyle.version>10.21.1</puppycrawl.checkstyle.version>
 
         <!-- Asciidoctor -->