[lworld] RFR: 8293038: [lworld] consolidate Value Objects tests

[Vicente Romero]

Refactoring tests, combining several regression tests into one test that uses the same test library we have used for records and sealed types. This way the overhead of adding new tests is reduced a lot. I also detected several issues on the existing tests with this refactoring, like repeated tests, etc.

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Commit messages:
 - more whitespace removed
 - removing whitespace
 - consolidate Value Objects tests
 - Merge branch 'lworld' into JDK-8293038
 - 8293038: [lworld] consolidate Value Objects tests

Changes: https://git.openjdk.org/valhalla/pull/733/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=733&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293038
  Stats: 1042 lines in 26 files changed: 504 ins; 538 del; 0 mod
  Patch: https://git.openjdk.org/valhalla/pull/733.diff
  Fetch: git fetch https://git.openjdk.org/valhalla pull/733/head:pull/733

PR: https://git.openjdk.org/valhalla/pull/733