Katalon plugin bundles Katalon utils:

https://github.com/jenkinsci/katalon-plugin/blob/4d1d9a53b0212051eedf39d9742afb307647a752/pom.xml#L88-L92

Katalon utils is licensed under a non-free license:

https://github.com/katalon-studio/utils/blob/b0839905e41b065f3c3c697bef7eb5e8ab4fd060/pom.xml#L41-L47

All software published by the Jenkins project must be licensed under an OSI approved open source license. This applies to all bundled libraries as well. Docs at https://www.jenkins.io/doc/developer/publishing/preparation/#license