Restore JCasC compatibility for JNLPLauncher.tunnel

[jglick]

#8762 seems to have broken JCasC compatibility for agent definitions using tunnel, which is probably unusual but happened to be used by an integration test in CloudBees CI.

I suspect the reason is that DataBoundConfigurator is buggy and does not support @DataBoundSetter on fields, which despite the name is supported by Jenkins core: it never actually looks for this annotation, and perhaps just assumes that getter/setter pairs not covered by the @DataBoundConstructor are properties.

Testing done

jenkinsci/configuration-as-code-plugin#2441

Removal of @Deprecated seems to only be necessary for compatibility with CloudBees CI, which has its own CasC reflection code not based on JCasC and which appears to check for the @Deprecated annotation on fields rather than on setters. (For @cloudbees only: verified running selected tests in the com.cloudbees.casc.server.items package.)

Proposed changelog entries

• The tunnel property on an inbound agent was inadvertently broken for JCasC usage in 2.437. It remains deprecated and usages should be deleted (regression in 2.437).

Proposed upgrade guidelines

N/A

Maintainer checklist

• There are at least two (2) approvals for the pull request and no outstanding requests for change.
• Conversations in the pull request are over, or it is explicit that a reviewer is not blocking the change.
• Changelog entries in the pull request title and/or Proposed changelog entries are accurate, human-readable, and in the imperative mood.
• Proper changelog labels are set so that the changelog can be generated automatically.
• If the change needs additional upgrade steps from users, the upgrade-guide-needed label is set and there is a Proposed upgrade guidelines section in the pull request title (see example).
• If it would make sense to backport the change to LTS, a Jira issue must exist, be a Bug or Improvement, and be labeled as lts-candidate to be considered (see query).

[MarkEWaite]

This PR is now ready for merge. We will merge it after approximately 24 hours if there is no negative feedback.

stale

[jglick]

java.lang.OutOfMemoryError: Java heap space on jenkins-war again

[MarkEWaite]

java.lang.OutOfMemoryError: Java heap space on jenkins-war again

Reported to the infra help desk as:

• Intermittent out of memory for Java 21 builds of Jenkins core on ci.jenkins.io jenkins-infra/helpdesk#3874

[timja]

/label ready-for-merge

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This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!