RFR: 8352628: Refine Grapheme test

[Naoto Sato]

Refining regex tests for Grapheme break so that every test case will run even with some failing ones.

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Commit messages:
 - initial commit

Changes: https://git.openjdk.org/jdk/pull/24168/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24168&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352628
  Stats: 84 lines in 1 file changed: 1 ins; 4 del; 79 mod
  Patch: https://git.openjdk.org/jdk/pull/24168.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24168/head:pull/24168

PR: https://git.openjdk.org/jdk/pull/24168