Upgrade checkstyle to 12.3.0

[holgerfriedrich]

Upgrade checkstyle from 10.26.1 to 12.3.0

Changlog:
https://github.com/checkstyle/checkstyle/releases/

Depends on #535

Outdated:
@wborn, @kaikreuzer
Checkstyle 11 requires Java 17.
How do we proceed?

I cannot remember right now why we still require Java 11 here. Can you pls. give me a hint?

[wborn]

See openhab/openhab-distro#1540

[holgerfriedrich]

@wborn, thanks!
Couldn't we switch to this fork https://mvnrepository.com/artifact/io.github.mavenplugins/unleash-maven-plugin/3.3.0 as mentioned openhab/openhab-distro#1475 (comment)?

Where do we define the version and source of the unleash plugin? Is one from the infrastructure-repo used? (Sorry, cannot see the connection yet. Is it pulled in in the Jenkins job only?)

[wborn]

It's in the super POM:

https://github.com/openhab/infrastructure/blob/584bc58b00260c73613c51f13bfb55cf784ba3c3/pom.xml#L59

We probably want to override the version and test it in the sandbox build first, before going through the hassle of releasing the super POM and finding out there are issues.

We also need to make sure it works with 4.3.x, 5.0.x branches or release a super POM with a version outside of the ranges used by those branches.

[lsiepel]

PR can be adapted to 12.3.0

[holgerfriedrich]

Yes, already done locally, but waiting for #535.