[lworld] Integrated: 8368022: serviceability/dcmd/gc/HeapDumpParallelTest.java fails missing output

[Alex Menkov]

Updates test to accept different logging variations

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Commit messages:
 - fix

Changes: https://git.openjdk.org/valhalla/pull/1625/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1625&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8368022
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/valhalla/pull/1625.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1625/head:pull/1625

PR: https://git.openjdk.org/valhalla/pull/1625