[jdk21u] RFR: 8315051: jdk/jfr/jvm/TestGetEventWriter.java fails with non-JVMCI GCs

[Aleksey Shipilev]

Clean backport to fix the failing test.

Additional testing:
 - [x] Affected test used to fail, now passes

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

Commit messages:
 - Backport 145d8bc1a3ef4f4fe0c10385be111838e7ed9250

Changes: https://git.openjdk.org/jdk21u/pull/125/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk21u&pr=125&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315051
  Stats: 28 lines in 1 file changed: 24 ins; 3 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u/pull/125.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u.git pull/125/head:pull/125

PR: https://git.openjdk.org/jdk21u/pull/125