[jdk21u-dev] RFR: 8352926: New test TestDockerMemoryMetricsSubgroup.java fails

[Sergey Chernyshev]

These are clean backports of JDK-8352926 and it's follow up fix JDK-8360533.

JDK-8352926 and JDK-8360533 are follow up fixes for JDK-8343191 (#2278)

This PR depends on and can be integrated after #2279

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

Depends on: https://git.openjdk.org/jdk21u-dev/pull/2279

Commit messages:
 - Backport 97ec9d3e0a6e3455579b567e1f58026f5b168c09
 - Backport 9ca1004e76a614328cd2eb7546143839c4d2f810

Changes: https://git.openjdk.org/jdk21u-dev/pull/2280/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=2280&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352926
  Stats: 127 lines in 3 files changed: 124 ins; 3 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/2280.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/2280/head:pull/2280

PR: https://git.openjdk.org/jdk21u-dev/pull/2280