[jdk17u-dev] RFR: 8316193: jdk/jfr/event/oldobject/TestListenerLeak.java java.lang.Exception: Could not find leak

[Daniel Hu]

Clean backport; already [backported to 21](https://github.com/openjdk/jdk21u-dev/pull/918). Improves jdk/jfr/event/oldobject/TestListenerLeak test making it more robust. Passes affected test.

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Commit messages:
 - Backport f6be922952642f40dcf0d27b7896c9a6acdd6378

Changes: https://git.openjdk.org/jdk17u-dev/pull/2821/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2821&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316193
  Stats: 12 lines in 1 file changed: 2 ins; 0 del; 10 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2821.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2821/head:pull/2821

PR: https://git.openjdk.org/jdk17u-dev/pull/2821