Configure eslint for warnings-ng to report on CI

[timja]

see jenkinsci/plugin-pom#874

Depends on jenkins-infra/pipeline-library#883 pipeline library to add:
https://github.com/jenkinsci/jenkins/blob/master/Jenkinsfile#L175C33-L179

and jenkinsci/plugin-pom#1016

Testing done

Introduced lint warnings locally with both CI and not CI.
Tested with PR of pipeline library showing that reporting is correct
Tested with SNAPSHOT of parent pom showing that new opt-in method works:

# -Dtest for a faster build, it still runs the frontend tests
mvn test -Dtest=org.jenkins_ci.plugins.workflow.workflow_cps.InjectedTest -Dmaven.test.failure.ignore

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

[timja]

@jglick any thoughts on bumping to parent pom 5.0? Requires updating the minimum jenkins.version to 2.479.