RFR: JDK-8289798: Update to use jtreg 7 [v6]

[Christian Stein]

On Mon, 5 Sep 2022 06:36:04 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

> Is jtreg 7 downward compatible? Can I use it to test older JDKs, if yes, down to which version?

Yes, down to JDK 11.

Quote from [Coming soon: jtreg 7](https://mail.openjdk.org/pipermail/jdk-dev/2022-August/006869.html)

> Also starting with version 7, jtreg is compiled with JDK 11 and so requires a recent release of JDK 11 to run it.

And it should have said more correctly: _...requires a recent release of JDK 11 **or later** to run it._

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PR: https://git.openjdk.org/jdk/pull/9393