[jdk17u] RFR: 8274521: jdk/jfr/event/gc/detailed/TestGCLockerEvent.java fails when other GC is selected

[Aleksey Shipilev]

Clean backport to improve testing.

Additional testing:
 - [x] Linux x86_64 fastdebug, affected test still passes (default)
 - [x] Linux x86_64 fastdebug, affected test still passes (G1)
 - [x] Linux x86_64 fastdebug, affected test is now ignored (Shenandoah)

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Commit messages:
 - Backport 0828273b898cca5368344e75f1c3f4c3a29dde80

Changes: https://git.openjdk.java.net/jdk17u/pull/256/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=256&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274521
  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/256.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/256/head:pull/256

PR: https://git.openjdk.java.net/jdk17u/pull/256