RFR: 8324868: debug agent does not properly handle interrupts of a virtual thread

[Chris Plummer]

Fix numerous debug agent issues and testing deficiencies related to Thread.interrupt(). As a first read you should look at the description in the CR. More details in first comment below.

Also, this PR is dependent on the fix for [JDK-8325187](https://bugs.openjdk.org/browse/JDK-8325187). The test might generate GHA failures in the meantime.

Tested with all svc tier1, tier2, and tier5 tests.

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Commit messages:
 - Undo some test changes that were suppose to be temporary
 - Improved debug agent thread interrupt handling

Changes: https://git.openjdk.org/jdk/pull/17989/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17989&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8324868
  Stats: 299 lines in 3 files changed: 173 ins; 62 del; 64 mod
  Patch: https://git.openjdk.org/jdk/pull/17989.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17989/head:pull/17989

PR: https://git.openjdk.org/jdk/pull/17989