Require Maven 3.9.6 or later

[Vlatombe]

See jenkinsci/maven-hpi-plugin#668

Testing done

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• 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

[MarkEWaite]

Thanks! We've been running Apache Maven 3.9.9 and its predecessor versions on ci.jenkins.io and its friends (like release.ci.jenkins.io) since those versions were released. No issues detected as far as I recall.

[basil]

Thanks for the PR!