fix(jenkins) Simplify Jenkinsfile

[gounthar]

As per @MarkEWaite 's earlier proposal, now tests Java 11 with a recent LTS, Java 17 even more recent.

• [X] Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• [X] Ensure that the pull request title represents the desired changelog entry
• [X] Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue