RFR: 8345937: Update JUnit Platform to newest version

[Marius Hanl]

The JUnit Platform got some updates over the last years, so it is a good idea to update it to the newest version.

That is from `5.8.1` to `5.11.3`.
Affected dependencies:
- `junit.jupiter`
- `junit.platform`
- `opentest4j`

Release notes: https://junit.org/junit5/docs/5.11.3/release-notes/

Note:
I did a handful of CI runs and got a test failure once in `ServiceLifecycleTest`. Not sure yet if related to the update or not.

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Commit messages:
 - Update JUnit Platform to newest version

Changes: https://git.openjdk.org/jfx/pull/1662/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1662&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8345937
  Stats: 54 lines in 2 files changed: 0 ins; 0 del; 54 mod
  Patch: https://git.openjdk.org/jfx/pull/1662.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1662/head:pull/1662

PR: https://git.openjdk.org/jfx/pull/1662