RFR: 8350964: Add an ArtifactResolver.fetch(clazz) method [v3]

[Matthew Donovan]

> In this PR, I created a new method, `ArtifactResolver.fetchOne()`, to consolidate duplicate code across tests.

Matthew Donovan has updated the pull request incrementally with one additional commit since the last revision:

  Changed ArtifactResolver.fetchOne() to throw a skipped exception

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23989/files
  - new: https://git.openjdk.org/jdk/pull/23989/files/83d479cb..4791105e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23989&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23989&range=01-02

  Stats: 28 lines in 4 files changed: 3 ins; 16 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/23989.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23989/head:pull/23989

PR: https://git.openjdk.org/jdk/pull/23989