RFR: 8369049: [TestBug] Update JUnit to Version 6.0.1 [v2]

[Marius Hanl]

> JUnit 6.0.1 is out and we can consider updating to it.
> 
> Release Notes: https://docs.junit.org/current/release-notes/index.html#release-notes-6.0.0
> https://docs.junit.org/current/release-notes/index.html#release-notes-6.0.1
> 
> Notes:
> - Java 17 is the baseline (so not a problem for us, since we have a higher baseline)
> - Deprecation were removed (not a problem, as we don't rely on any)
> - JUnit Vintage Engine is deprecated (not a problem, as we dropped support for it some months ago)
> 
> JUnit 6 now uses a single version number for all dependencies, that is platform, jupiter and vintage (which we do not use anymore). That makes updating it easier.
> 
> It also uses `JSpecify`, which is an annotation library for `@NonNull` and `@Nullable`. All version numbers for JUnit now use a single variable.

Marius Hanl has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - 6.0.1
 - Merge branch 'master' of https://github.com/openjdk/jfx into junit6-upgrade
 - Update to JUnit Version 6.0.0

-------------

Changes:
  - all: https://git.openjdk.org/jfx/pull/1925/files
  - new: https://git.openjdk.org/jfx/pull/1925/files/a41489c9..e28215be

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1925&range=01
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1925&range=00-01

  Stats: 3244 lines in 154 files changed: 2348 ins; 299 del; 597 mod
  Patch: https://git.openjdk.org/jfx/pull/1925.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1925/head:pull/1925

PR: https://git.openjdk.org/jfx/pull/1925