RFR: 7903581: Typo in make file in pandoc binary detection

[Jaikiran Pai]

Can I please get a review of this change which fixes a in typo in `pandoc` binary detection in the make file? This addresses https://bugs.openjdk.org/browse/CODETOOLS-7903581

-------------

Commit messages:
 - copyright year
 - 7903581: Typo in make file in pandoc binary detection

Changes: https://git.openjdk.org/jtreg/pull/174/files
 Webrev: https://webrevs.openjdk.org/?repo=jtreg&pr=174&range=00
  Issue: https://bugs.openjdk.org/browse/CODETOOLS-7903581
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jtreg/pull/174.diff
  Fetch: git fetch https://git.openjdk.org/jtreg.git pull/174/head:pull/174

PR: https://git.openjdk.org/jtreg/pull/174