[FLINK-39007] Run RAT plugin in downstream projects automatically

[ferenc-csaky]

Key Changes

• Add RAT plugin under build -> plugins
• Removed setting inherited to false, as that setting forbids downstream project to execute the defined configuration here
• Exclude test resources from license checks

[leonardBang]

+1

[davidradl]

@ferenc-csaky I see the change is for the parent pom i.e. the Flink version 2 based parent we have just added. Can we add this to the version 1 and 1.1 versions which all the current connectors use?

[ferenc-csaky]

@davidradl Since we do not have different branches for the parent POM state, currently we have the 2.x line and that's it. We can introduce different branches for release lines (or just create a tag from a local patch), but I'd start a discussion for that and the deatils in the dev channel. But personally I'd rather not.

This parent POM has 1-2 relevant changes per year, and those are pretty much dependency bumps, so keeping this simple and minimizing maintenance is more important IMO. I added a manual license check step to the connector releasing docs, which I would consider good enough.

[davidradl]

@davidradl Since we do not have different branches for the parent POM state, currently we have the 2.x line and that's it. We can introduce different branches for release lines (or just create a tag from a local patch), but I'd start a discussion for that and the deatils in the dev channel. But personally I'd rather not.

This parent POM has 1-2 relevant changes per year, and those are pretty much dependency bumps, so keeping this simple and minimizing maintenance is more important IMO. I added a manual license check step to the connector releasing docs, which I would consider good enough.

OK sounds reasonable.