RFR: Future-proof mbox test

[Robin Westberg]

Hi all,

Please review this minor test case fix that fixes a time related failure.

Best regards,
Robin

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Commits:
 - 193caa0a: Future-proof mbox test

Changes: https://git.openjdk.java.net/skara/pull/156/files
 Webrev: https://webrevs.openjdk.java.net/skara/156/webrev.00
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/skara/pull/156.diff
  Fetch: git fetch https://git.openjdk.java.net/skara pull/156/head:pull/156

PR: https://git.openjdk.java.net/skara/pull/156