RFR: 8333108: Update vmTestbase/nsk/share/DebugeeProcess.java to don't use finalization

[Leonid Mesnik]

The 
test/hotspot/jtreg/vmTestbase/nsk/share/jpda/DebugeeProcess.java
uses cleanup() to kill debuggee process.

However, most tests kill the debuggee process explicitly. I verified that debuggee process is killed before test finishes. (Just by printing it's status.)

The fix adds a few checks debuggee.waitFor() int tests that didn't check debuggee process code.

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Commit messages:
 - 8333108: Update vmTestbase/nsk/share/DebugeeProcess.java to don't use finalization

Changes: https://git.openjdk.org/jdk/pull/19437/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19437&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8333108
  Stats: 42 lines in 6 files changed: 16 ins; 21 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/19437.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19437/head:pull/19437

PR: https://git.openjdk.org/jdk/pull/19437