[jdk11u-dev] RFR: 8287663: Add a regression test for JDK-8287073

[Severin Gehwolf]

Clean backport after "[JDK-8287107](https://bugs.openjdk.org/browse/JDK-8287107): CgroupSubsystemFactory.setCgroupV2Path asserts with freezer controller". Mostly a regression test, low risk.

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Depends on: https://git.openjdk.org/jdk11u-dev/pull/1340

Commit messages:
 - 8287663: Add a regression test for JDK-8287073

Changes: https://git.openjdk.org/jdk11u-dev/pull/1341/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1341&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8287663
  Stats: 36 lines in 2 files changed: 35 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1341.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1341/head:pull/1341

PR: https://git.openjdk.org/jdk11u-dev/pull/1341