Update dependency com.puppycrawl.tools:checkstyle to v10.21.4 (jenkinsci#2649)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

pom.xml

@@ -72,7 +72,7 @@
             <dependency>
               <groupId>com.puppycrawl.tools</groupId>
               <artifactId>checkstyle</artifactId>
-              <version>10.21.3</version>
+              <version>10.21.4</version>
             </dependency>
           </dependencies>
         </plugin>