[jdk17u-dev] RFR: 8290041: ModuleDescriptor.hashCode is inconsistent

[Goetz Lindenmaier]

I backport this follow-up to JDK-8294427

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Commit messages:
 - Backport 4cc6cb9d9ddbcc540baac7b81398f2af83f93340

Changes: https://git.openjdk.org/jdk17u-dev/pull/2220/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2220&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8290041
  Stats: 123 lines in 2 files changed: 117 ins; 3 del; 3 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2220.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2220/head:pull/2220

PR: https://git.openjdk.org/jdk17u-dev/pull/2220