[jdk11u-dev] RFR: 8310818: Refactor more Locale tests to use JUnit

[Andrew Lu]

I backport this for parity with 11.0.24-oracle.

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Commit messages:
 - Backport 989e0bfe59d67f6a751e8b187caabbd0fd8c8f81

Changes: https://git.openjdk.org/jdk11u-dev/pull/2693/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2693&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8310818
  Stats: 1939 lines in 13 files changed: 679 ins; 1250 del; 10 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2693.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2693/head:pull/2693

PR: https://git.openjdk.org/jdk11u-dev/pull/2693