RFR: JDK-8327071: [Testbug] g-tests for cgroup leave files in /tmp on linux

[Arno Zeller]

After each run of the g-tests for cgroups on Linux there are three new files left in /tmp.

cgroups-test-jdk.pid<pid>.cgroupTest.SubSystemFileLineContentsSingleLine
cgroups-test-jdk.pid<pid>.cgroupTest.SubSystemFileLineContentsMultipleLinesSuccessCases
cgroups-test-jdk.pid<pid>.cgroupTest.SubSystemFileLineContentsMultipleLinesErrorCases

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Commit messages:
 - Fix comment as requested by mbaesken
 - Merge branch 'openjdk:master' into JDK-8327071
 - JDK-8327071

Changes: https://git.openjdk.org/jdk/pull/18077/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18077&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8327071
  Stats: 10 lines in 1 file changed: 9 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18077.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18077/head:pull/18077

PR: https://git.openjdk.org/jdk/pull/18077