Update NullLogWriter to migrate NullOutputStream to INSTANCE

[JinwooHwang]

For all changes:

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[raboof]

It would be good to mention the motivation for the change in the PR.

In this case indeed NULL_OUTPUT_STREAM has been deprecated in favour of INSTANCE (https://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/output/NullOutputStream.html)

[raboof]

It would be good to mention the motivation for the change in the PR.

In this case indeed NULL_OUTPUT_STREAM has been deprecated in favour of INSTANCE (https://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/output/NullOutputStream.html)

OK looks like the motivation is just "I wanted to update commons-io and had to fix this deprecation error" - simple, but still would be worth mentioning :)

[JinwooHwang]

Yes, that’s exactly it, @raboof. I just wanted to update commons-io and needed to address the deprecation error along the way. Thank you for pointing out that it’s worth mentioning — I really appreciate the reminder, I’ll be sure to note it more clearly next time.

[raboof]

Now that the main branch is green after #7916 I'm confident any regressions caused by the update will be noticed, so this LGTM.

[raboof]

@JinwooHwang-SAS this caused a failure of the integration tests in https://github.com/apache/geode/actions/runs/17291015222/job/49079826921 - looks like the version update needs to be registered somewhere else as well? Could you follow up?

[JinwooHwang]

I have addressed the issue via 7ee1fbe, @raboof . Thank you.

[raboof]

cool - is that commit in a PR somewhere yet? (also the comment seems to mention beanutils instead of io)

[JinwooHwang]

@raboof . Yes, I made the update while working on PR #7904. In hindsight, it would have been much clearer to include it in PR #7902, and I sincerely apologize for that oversight. Thank you very much for catching this and for your patience — I truly appreciate your guidance and support throughout the review.