[jdk11u-ri] RFR: 8301401: 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 11 (https://mail.openjdk.org/pipermail/jdk-updates-dev/2023-February/020724.html). The RI contains a portion of previously released Maintenance Release 1 of the Java SE 11 (Unicode Characters) updates as well. (https://jcp.org/aboutJava/communityprocess/maintenance/jsr384/jsr384-mr1-changes.html#s3)

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Commit messages:
 - Removed trailing whitespace
 - Fixed test headers
 - Add tests and update test binary for GB18030-2022
 - Fixed incorrect script range / copyright year
 - Dropped the table
 - 8301401: Allow additional characters for GB18030-2022 support
 - 8211398: Square character support for the Japanese new era

Changes: https://git.openjdk.org/jdk11u-ri/pull/2/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-ri&pr=2&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301401
  Stats: 385 lines in 8 files changed: 366 ins; 2 del; 17 mod
  Patch: https://git.openjdk.org/jdk11u-ri/pull/2.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-ri pull/2/head:pull/2

PR: https://git.openjdk.org/jdk11u-ri/pull/2