RFR: 7903671: jcstress: Update buffer tests for JDK-8318966

[Jiří Vaněk]

part 1:  Detecting jdk of target VM and exuding illegible tests

This is prequel to full fixing of CODETOOLS-7903671. This PR detects target JDK version and then disables illegible tests.
part 2 will be done in templates of affected tests and logic around generating the classes from them. In meantime this should server.

The jdk detection will be most likely used anyway. WDYT? If we agree on similar approach, I will create a new bug for this PR only.

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Commit messages:
 - Excluding jdk23+ illegible tests on jdk23+
 - Added  detection on target JDK version

Changes: https://git.openjdk.org/jcstress/pull/159/files
  Webrev: https://webrevs.openjdk.org/?repo=jcstress&pr=159&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903671
  Stats: 129 lines in 3 files changed: 121 ins; 1 del; 7 mod
  Patch: https://git.openjdk.org/jcstress/pull/159.diff
  Fetch: git fetch https://git.openjdk.org/jcstress.git pull/159/head:pull/159

PR: https://git.openjdk.org/jcstress/pull/159