[jdk8u-ri] RFR: 8301400: Allow additional characters for GB18030-2022 support

[Naoto Sato]

Please review the changes to the Reference Implementation of the proposed Maintenance Release of the Java SE 8 (https://mail.openjdk.org/pipermail/jdk8u-dev/2023-February/016710.html)

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Commit messages:
 - Fixed test headers
 - Update test and test binary for GB18030-2022
 - Copyright year
 - Dropped the table
 - 8301400: Allow additional characters for GB18030-2022 support
 - 8211398: Square character support for the Japanese new era

Changes: https://git.openjdk.org/jdk8u-ri/pull/10/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk8u-ri&pr=10&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301400
  Stats: 367 lines in 5 files changed: 356 ins; 0 del; 11 mod
  Patch: https://git.openjdk.org/jdk8u-ri/pull/10.diff
  Fetch: git fetch https://git.openjdk.org/jdk8u-ri pull/10/head:pull/10

PR: https://git.openjdk.org/jdk8u-ri/pull/10