[code-reflection] Integrated: cleaned up test stanza of hat.java test

[Gary Frost]

Cleaned up `test` stanza of hat.java.

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Commit messages:
 - cleaned up test stanza of hat.java test

Changes: https://git.openjdk.org/babylon/pull/569/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=569&range=00
  Stats: 95 lines in 1 file changed: 1 ins; 45 del; 49 mod
  Patch: https://git.openjdk.org/babylon/pull/569.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/569/head:pull/569

PR: https://git.openjdk.org/babylon/pull/569