RFR: 8037914: Add JFR event for string deduplication [v8]

[Erik Gahlin]

On Mon, 17 Nov 2025 14:45:29 GMT, Francesco Andreuzzi <fandreuzzi at openjdk.org> wrote:

>> In this PR I introduce a new JFR event: `jdk.StringDeduplication`
>> 
>> The new event is emitted every time a deduplication cycle happens.
>> 
>> Passes tier1 and tier2 (fastdebug).
>
> Francesco Andreuzzi has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix year

Marked as reviewed by egahlin (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/28015#pullrequestreview-3474120613