[4diac-dev] Upgrade 4diac IDE Jenkins builds to Java 17

[Alois Zoitl <alois.zoitl@xxxxxx>]

Hi,

over the last days I worked on upgrading 4diac IDE to Eclipse 2022-09. As part of the upgrade I also upgraded Eclipse Tycho to 3.0.0. As Eclipse Tycho requires
now Java 17 to build I'm also in the process of upgrading our Jenkins builds to openJDK17-latest. While we are using Java 17 to build we are still building with
Java 11 as target. The reason for this is that XText currently is not able to handle Java versions newer then 11 [1]. As soon as this is fixed I would also try
to fully upgrade 4diac IDE to Java 17.

I hope you don't see any issues for that process. 

Cheers,
Alois

[1] https://github.com/eclipse/xtext/issues/1982