Hello all,the checkstyle version has been bumped to 8.12. If you're checkstyle in IntelliJ (according to out guide <https://ci.apache.org/projects/flink/flink-docs-master/flinkDev/ide_setup.html#checkstyle-for-java>) then you also have to manually set the version in IntelliJ to 8.12, as described in step 4.
Sorry for the inconvenience.
