RFR: 7904068: Update to use JUnit 5.13 [v2]

[Christian Stein]

> Please review this change updating to use JUnit 5.13.4

Christian Stein has updated the pull request incrementally with one additional commit since the last revision:

  Fail if JUnit could not find any test

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Changes:
  - all: https://git.openjdk.org/apidiff/pull/30/files
  - new: https://git.openjdk.org/apidiff/pull/30/files/22325c08..7f22edd2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=apidiff&pr=30&range=01
 - incr: https://webrevs.openjdk.org/?repo=apidiff&pr=30&range=00-01

  Stats: 1 line in 1 file changed: 1 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/apidiff/pull/30.diff
  Fetch: git fetch https://git.openjdk.org/apidiff.git pull/30/head:pull/30

PR: https://git.openjdk.org/apidiff/pull/30