+ drop the OOB support for Jetty 9.4.x
+ simplify Jenkinsfile since master now builds with Java 11

* Revert to Java 14 since Spoon doesn't work with Java 16....

[Misc] Try to work around the "Java heap space" issue when using the maven assembly plugin for building the hsqldb/jetty flavor. See https://tinyurl.com/45dzmyek
* Roll back the change to see if it helps with the "Killed" job issue

[Misc] Try to work around the "Java heap space" issue when using the maven assembly plugin for building the hsqldb/jetty flavor. See https://tinyurl.com/45dzmyek
* Reduce a bit the memory added since it seems this could be why we now have "Killed" builds in the CI...

[Misc] Try to work around the "Java heap space" issue when using the maven assembly plugin for building the hsqldb/jetty flavor. See https://tinyurl.com/45dzmyek

[Misc] Remove wrong removal of the "repository-all" profile since we need nexus.xwiki.org for the xwiki deps

* Fix bad syntax (again)

* Fix bad syntax

* Add missing commas

[Misc] Make the IT test a real IT test (using the failsafe maven plugin), so that it's executed only once on the CI (for example)
* Differentiate the build name too.

[Misc] Temporarily revert the improvement to the trigger logic (by only checking the first previus non-docker build) since it's currently not working for some reason I cannot understand and I'm going on holidays

[Misc] Only check the previous non-docker build for deciding whether to execute a new docker build or not

[Misc] Add debug logs to try to understand why docker-latest didn't run last night even thought the previous job was SCM-triggered

[Misc] Replace checking for a non-empty changeset by checking that the previous build was triggrered by a SCM change

[Misc] Don't set the build as successful when the docker build is not executed + always build when triggered manually

[Misc] Start docker-latest jobs at 10PM to give me more time during the night so that by the morning they're done