[jdk21u-dev] RFR: 8334320: Replace vmTestbase/metaspace/share/TriggerUnloadingWithWhiteBox.java with ClassUnloadCommon from testlibrary [v2]

[Goetz Lindenmaier]

> I backport this for parity with 21.0.9-oracle.
> 
> Resolved copyright as 8345795: Update copyright year to 2024 for hotspot in files where it was missed is not in 21/17.
> 
> Probably clean anyways.

Goetz Lindenmaier has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains one new commit since the last revision:

  Backport 9b49597244f898400222cfc252f50a2401ca3e2f

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Changes:
  - all: https://git.openjdk.org/jdk21u-dev/pull/1945/files
  - new: https://git.openjdk.org/jdk21u-dev/pull/1945/files/b550fe24..cd7ff649

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1945&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1945&range=00-01

  Stats: 36 lines in 1 file changed: 36 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1945.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1945/head:pull/1945

PR: https://git.openjdk.org/jdk21u-dev/pull/1945