[JENKINS-52019] - Update Groovy from 2.4.11 to 2.4.12 to pick up fixes towards Java 11 support

[oleg-nenashev]

See JENKINS-52019, it is a core counterpart for jenkinsci/workflow-support-plugin#68. Requires sign-off from @svanoort before going forward

Testing:

• Spot-check during the Java 10+ hackathon (on Java 8, 10, 11)
• Soak testing on @oleg-nenashev's environment (~2 weeks, Java 8)
• Testing for memory leaks by @svanoort . Originally we suspected a memory leak, but according to tests there is no evidence of that which would block the change upstreaming

Proposed changelog entries

• RFE Update Groovy from 2.4.11 to 2.4.12 to pick up fixes towards Java 11 support
  • http://groovy-lang.org/changelogs/changelog-2.4.12.html

Submitter checklist

• JIRA issue is well described
• Changelog entry appropriate for the audience affected by the change (users or developer, depending on the change). Examples
  * Use the Internal: prefix if the change has no user-visible impact (API, test frameworks, etc.)
• Appropriate autotests or explanation to why this change has no tests
• For dependency updates: links to external changelogs and, if possible, full diffs

Desired reviewers

@jenkinsci/sig-platform @svanoort

[daniel-beck]

🎉

[svanoort]

I'm approving, but we should watch feedback on the weekly carefully just in case (we cannot readily cover every possible Groovy failure mode

[oleg-nenashev]

we should watch feedback on the weekly carefully just in case (we cannot readily cover every possible Groovy failure mode

for sure

[oleg-nenashev]

Merging. It has been soak tested for long, and it makes sense to proceed so we have more time for evaluation before LTS