RFR: 8327136: javax/management/remote/mandatory/notif/NotifReconnectDeadlockTest.java fails on libgraal

[Doug Simon]

To account for slightly slower compile times on libgraal + fastdebug + `-Xcomp`, this PR increases a timeout in `NotifReconnectDeadlockTest.java` from 2000 ms to 3000 ms.
With this change, the test now reliably passes.

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Commit messages:
 - adjust timeout in NotifReconnectDeadlockTest.java

Changes: https://git.openjdk.org/jdk/pull/18085/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18085&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8327136
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/18085.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18085/head:pull/18085

PR: https://git.openjdk.org/jdk/pull/18085