[jdk11u-dev] RFR: 8315437: Enable parallelism in vmTestbase/nsk/monitoring/stress/classload tests

[Andrew Lu]

I backport this for parity with 11.0.25-oracle.

-------------

Commit messages:
 - Backport dd214d0f9543f125ef514eb3a60a65a5f514b1ca

Changes: https://git.openjdk.org/jdk11u-dev/pull/2759/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2759&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315437
  Stats: 552 lines in 24 files changed: 0 ins; 552 del; 0 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2759.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2759/head:pull/2759

PR: https://git.openjdk.org/jdk11u-dev/pull/2759