[jdk26u] RFR: 8376485: Update the release version and date for OpenJDK 26u

[Nibedita Jena]

Update the release version for OpenJDK 26u

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Commit messages:
 - 8376485: Update the release version and date for OpenJDK 26u

Changes: https://git.openjdk.org/jdk26u/pull/31/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk26u&pr=31&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8376485
  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk26u/pull/31.diff
  Fetch: git fetch https://git.openjdk.org/jdk26u.git pull/31/head:pull/31

PR: https://git.openjdk.org/jdk26u/pull/31