RFR: 8373913: Refactor serialization tests to use JUnit [v5]

[Justin Lu]

On Tue, 13 Jan 2026 18:00:23 GMT, Roger Riggs <rriggs at openjdk.org> wrote:

>> Refactor serialization tests to use JUnit.
>> Automated conversion for most annotations.
>> Conditional tests are refactored to use JUnit Enable/DisableIf.
>
> Roger Riggs has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Review suggestions to remove extra spaces, duplicate annotation, and
>   the last remaining use of PER_CLASS.

LGTM

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Marked as reviewed by jlu (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/28877#pullrequestreview-3657340540