[jdk17u-dev] RFR: 8320921: GHA: Parallelize hotspot_compiler test jobs

[Aleksey Shipilev]

Clean backport to make GHA testing faster.

Additional testing:
 - [ ] GHA

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Commit messages:
 - Backport 694136909c058370a5833322ebaf2e71a0a15164

Changes: https://git.openjdk.org/jdk17u-dev/pull/2099/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2099&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8320921
  Stats: 13 lines in 1 file changed: 10 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2099.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2099/head:pull/2099

PR: https://git.openjdk.org/jdk17u-dev/pull/2099