RFR: JDK-8316897: tools/jpackage/junit tests fail on AIX after JDK-8316547

[Matthias Baesken]

AIX currently does not have the jdk.jpackage system module. We have to take this into account for these jpackage tests.

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Commit messages:
 - JDK-8316897

Changes: https://git.openjdk.org/jdk/pull/15916/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15916&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316897
  Stats: 60 lines in 11 files changed: 60 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/15916.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15916/head:pull/15916

PR: https://git.openjdk.org/jdk/pull/15916