SystemPropertyTest in a fresh JVM, three times.

No -D flags:
  runOnlyHighSeverityTests() : SKIPPED  (System property [test.severity] does not exist)
  testEnglishLocalization() : PASSED

-Dtest.severity=high -Duser.language=fr  (the command line from the 2025 article):
  runOnlyHighSeverityTests() : PASSED
  testEnglishLocalization() : SKIPPED  (System property [user.language] with value [fr] does not match regular expression [en])

-Dtest.severity=low -Duser.language=en:
  runOnlyHighSeverityTests() : SKIPPED  (System property [test.severity] with value [low] does not match regular expression [critical|high])
  testEnglishLocalization() : PASSED
