[JENKINS-68941] Make -Dtest=... work again

[daniel-beck]

See JENKINS-68941. Amends #6652.

When running mvn clean install -Dspotbugs.skip -Dfindbugs.skip -Dcheckstyle.skip -Dspotless.check.skip -Dtest=PluginManagerTest, the cli module build fails without this, but passes with this change.

Proposed changelog entries

(Internal/developer only)

Proposed upgrade guidelines

N/A

Submitter checklist

• (If applicable) Jira issue is well described
• Changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developer, depending on the change) and are in the imperative mood. Examples
  • Fill-in the Proposed changelog entries section only if there are breaking changes or other changes which may require extra steps from users during the upgrade
• Appropriate autotests or explanation to why this change has no tests
• New public classes, fields, and methods are annotated with @Restricted or have @since TODO Javadoc, as appropriate.
• New deprecations are annotated with @Deprecated(since = "TODO") or @Deprecated(forRemoval = true, since = "TODO") if applicable.
• For dependency updates: links to external changelogs and, if possible, full diffs

Desired reviewers

@mention

Maintainer checklist

Before the changes are marked as ready-for-merge:

• There are at least 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 does not block the change
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• 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).

[basil]

The same is the case for plugins with a Maven multi-module build (e.g., pipeline-model-definition) and other core components with a Maven multi-module build (e.g., lib-access-modifier). I think this is a good idea but I think the right place to fix this is in plugin-pom and pom (the fact that both exist and are largely duplicates of each other is a pre-existing issue, but I try to keep them in sync as much as possible). That way, the fix would apply to the whole organization rather than just this repository. Not against applying it to this repository alone, but I view that as more of a hotfix than a long-term fix. Similar situation with the change James wanted to make recently about redirecting test output to a file: we ended up putting that in place in pom and plugin-pom rather than in core.

[daniel-beck]

Note that I am simply fixing what was broken by the update: The profile for this purpose exists and sets a (now apparently no longer correct) property. I would consider the migration of this behavior upstream a good idea, but out of scope of this PR.

[basil]

And I would consider short-term fixes like this acceptable, but not desirable.

[daniel-beck]

I guess superseded by jenkinsci/pom#274 and #6793