<i18n dev> RFR: 8315444: Convert test/jdk/tools to Classfile API

[Qing Xiao]

/test/jdk/tools/lib/tests/JImageValidator.java, tests in /test/jdk/tools/jlink and /test/jdk/tools/jimage use on com.sun.tools.classfile and should be converted to Classfile API.

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Commit messages:
 - migrate /test/jdk/tools/lib/tests/JImageValidator.java and tests in /test/jdk/tools/jlink and /test/jdk/tools/jimage use Classfile API

Changes: https://git.openjdk.org/jdk/pull/15529/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15529&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315444
  Stats: 168 lines in 23 files changed: 111 ins; 15 del; 42 mod
  Patch: https://git.openjdk.org/jdk/pull/15529.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15529/head:pull/15529

PR: https://git.openjdk.org/jdk/pull/15529