RFR: CODETOOLS-7903398: Incorrect format for version in error message

[Jonathan Gibbons]

Please review a simple update to use the new format for version strings, for use in an error message.

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Commit messages:
 - CODETOOLS-7903398: Incorrect format for version in error message

Changes: https://git.openjdk.org/jtreg/pull/143/files
 Webrev: https://webrevs.openjdk.org/?repo=jtreg&pr=143&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903398
  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jtreg/pull/143.diff
  Fetch: git fetch https://git.openjdk.org/jtreg pull/143/head:pull/143

PR: https://git.openjdk.org/jtreg/pull/143