[jdk21u-dev] RFR: 8312916: Remove remaining usages of -Xdebug from test/hotspot/jtreg

[Goetz Lindenmaier]

I backport this to keep the 21u test suite up-to-date. This will simplify future test backports.

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Commit messages:
 - Backport e9daf4a0185b90762d2bdd38d86fe93b4822ea08

Changes: https://git.openjdk.org/jdk21u-dev/pull/60/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=60&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8312916
  Stats: 6 lines in 3 files changed: 0 ins; 4 del; 2 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/60.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/60/head:pull/60

PR: https://git.openjdk.org/jdk21u-dev/pull/60