[jdk21u-dev] RFR: 8342098: Write a test to compare the images

[Goetz Lindenmaier]

I backport this for parity with 21.0.8-oracle

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Commit messages:
 - Backport 47ebf8d868b2e15b943a227ad3cf2ee12eed10f6

Changes: https://git.openjdk.org/jdk21u-dev/pull/1410/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1410&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8342098
  Stats: 166 lines in 1 file changed: 166 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1410.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1410/head:pull/1410

PR: https://git.openjdk.org/jdk21u-dev/pull/1410