Misconfigured Checkstyle Plug-in in Assemblies
Lars: The assemblies pom.xml files should reference the mail pom.xml and use the checkstyle-plugin version specified in there, not specifying their own version.
Basil: The only reason why I had to reference the checkstyle rules in the assemblies-POM again was because otherwise the files cannot be found by Maven. You can easily verify that by removing the configuration for the checkstyle-plugin from the assemblies-POM.
The checkstyle plugin configuration is only used to disable the
plug-in. It is otherwise misconfigured. Most importantly, it also
required a specific version of the plug-in, not depending on the version
in the main pom.xml.
I will provide a patch for this in a moment.
Fixed by commit fc2806bf9634f20e584adc4a72aaead12ca9be20 by