RFR: 8322219: GenShen: GHA for shenandoah repo should run all shenandoah jtreg tests

[William Kemper]

GHA for shenandoah repo should run all shenandoah jtreg tests

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Commit messages:
 - GHA for shenandoah repo should run all shenandoah jtreg tests

Changes: https://git.openjdk.org/shenandoah/pull/373/files
 Webrev: https://webrevs.openjdk.org/?repo=shenandoah&pr=373&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8322219
  Stats: 5 lines in 1 file changed: 5 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/shenandoah/pull/373.diff
  Fetch: git fetch https://git.openjdk.org/shenandoah.git pull/373/head:pull/373

PR: https://git.openjdk.org/shenandoah/pull/373