[jdk20u] RFR: 8306774: Make runtime/Monitor/GuaranteedAsyncDeflationIntervalTest.java more reliable [v3]

[Aleksey Shipilev]

> Backport the test reliability fix. The backport was not clean, because there was a conflict in `ProblemList` that took the test away from it. I saw no point in backporting the unclean addition to the problem-list, so this PR just omits any changes to a problemlist.
> 
> Additional testing: 
>  - [x] macos-aarch64-server-fastdebug, `runtime/Monitor`
>  - [x] Linux x86_64 fastdebug, `tier1 tier2 tier3` (together with #71)
>  - [x] Linux AArch64 fastdebug, `tier1 tier2 tier3` (together with #71)

Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:

 - Merge branch 'master' of https://git.openjdk.org/jdk20u into JDK-8306774-gadt-test-improv
 - Backport 9ad6dc881d285cc26c136f0ef19af5bac0a75022
 - Merge branch 'master' into JDK-8305994-guarantee-async-deflation
 - Backport 6b81342c2215041dbb7e9020a67cdc56976c97b1

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

Changes:
  - all: https://git.openjdk.org/jdk20u/pull/70/files
  - new: https://git.openjdk.org/jdk20u/pull/70/files/36ad8ad7..5606c01e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk20u&pr=70&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk20u&pr=70&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk20u/pull/70.diff
  Fetch: git fetch https://git.openjdk.org/jdk20u.git pull/70/head:pull/70

PR: https://git.openjdk.org/jdk20u/pull/70