RFR: 8345431: Detect duplicate entries in jar files with jar --validate [v5]

[Henry Jen]

> This PR check the jar file to ensure entries are consistent from the central directory and local file header. Also check there is no duplicate entry names that could override the desired content by accident.

Henry Jen has updated the pull request incrementally with one additional commit since the last revision:

  Validation entry name, also output the count of duplicates

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Changes:
  - all: https://git.openjdk.org/jdk/pull/24430/files
  - new: https://git.openjdk.org/jdk/pull/24430/files/e38774af..24d0776d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24430&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24430&range=03-04

  Stats: 229 lines in 3 files changed: 151 ins; 45 del; 33 mod
  Patch: https://git.openjdk.org/jdk/pull/24430.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24430/head:pull/24430

PR: https://git.openjdk.org/jdk/pull/24430