Fix NullPointerException in LazyBuildMixIn on jenkins reload

[dukhlov]

Fixes #26397

This PR removes the lazy loading behavior of RunMap’s entry.getValue(). The value will now be resolved inside iterator.next() instead of in entry.getValue() itself.

The weak semantics will be preserved for keySet() iteration, allowing iteration without resolving values on each step. Values can still be resolved explicitly by calling RunMap.get(someKey).

Testing done

Only jenkins integration tests. It is hard to reproduce the issue

Screenshots (UI changes only)

Before

After

Proposed changelog entries

• Partially revert optimisation in RunMap that causes issues when reloading

Proposed changelog category

/label regression-fix

Proposed upgrade guidelines

N/A

Submitter checklist

• The issue, if it exists, is well-described.
• The changelog entries and upgrade guidelines are appropriate for the audience affected by the change (users or developers, depending on the change) and are in the imperative mood (see examples). Fill in the Proposed upgrade guidelines section only if there are breaking changes or changes that may require extra steps from users during upgrade.
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Desired reviewers

@jglick

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

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.
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[timja]

Thanks for sorting so quickly. I've tweaked the changelog entry a bit, not entirely happy with but I think its better than before.

[jglick]

To be clear, is this reverting all or part of some specific prior PR?

[dukhlov]

To be clear, is this reverting all or part of some specific prior PR?

I would say that it's re-work of #11038

[timja]

/label ready-for-merge

---

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

Thanks!

[sxa]

Thanks for getting this fix done so quickly. I'm not too familiar with your LTS build cut-off dates but assuming it gets merged this week is it likely to make it into 2.541.3 in a couple of weeks from now?

[timja]

see #26397 (comment)