RFR: 7904068: Update to use JUnit 5.13

[Christian Stein]

Please review this change updating to use JUnit 5.13.4

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Commit messages:
 - Use correct order of arguments
 - Fix syntax
 - Use JUnit's `execute` command directly
 - Use correct SHA1 checksum
 - Update to use JUnit 5.13

Changes: https://git.openjdk.org/apidiff/pull/30/files
  Webrev: https://webrevs.openjdk.org/?repo=apidiff&pr=30&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7904068
  Stats: 5 lines in 2 files changed: 1 ins; 0 del; 4 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