RFR: 8366970: CPUTimeUsage: Add comment about usage during VM exit

[Jonas Norlinder]

On Fri, 5 Sep 2025 10:06:32 GMT, Jonas Norlinder <duke at openjdk.org> wrote:

> Some of the methods in CPUTimeUsage make a query on the underlying threads. Calling those methods during VM exit is therefore unsafe. This PR adds a comment to provide clarification.

Withdrawn in favor of using _is_shutting down introduced by 8366865

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PR Comment: https://git.openjdk.org/jdk/pull/27115#issuecomment-3325595230