<i18n dev> RFR: 8346944: Update Unicode Data Files to 17.0.0

[Naoto Sato]

Updates the JDK to use the latest Unicode 17.0.0, which also updates the ICU4J along with it ([8346947](https://bugs.openjdk.org/browse/JDK-8346947)
Update ICU4J to Version 78.1). The corresponding CSR has already been approved.

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Commit messages:
 - icudata path fix
 - Update versions
 - icu4j final
 - .md file changes
 - 17.0 final
 - icudata78b(binary)
 - CaseFolding.text -> 17, copyright symbol as is
 - icudt78b
 - 17-beta
 - initial commit

Changes: https://git.openjdk.org/jdk/pull/28093/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28093&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8346944
  Stats: 2977 lines in 35 files changed: 1345 ins; 650 del; 982 mod
  Patch: https://git.openjdk.org/jdk/pull/28093.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28093/head:pull/28093

PR: https://git.openjdk.org/jdk/pull/28093