RFR: 2327: Skip CheckTests.acceptSimpleMerges on older Git

[Pavel Rappo]

Please review this test fix.

A recently added test fails in environments with Git versions older than 2.36. This is because the test verifies functionality that uses `--remerge-diff` added to [Git 2.36]( https://github.blog/2022-04-18-highlights-from-git-2-36/).

Note that it's sufficient to conditionally skip the test. We don't need to amend the logic being tested, as bots are run on Git 2.36 or newer. The test assumes 2.36 as the minimum Git version. The test uses the existing functionality provided by `org.openjdk.skara.vcs.git.GitVersion`. Hope, that new dependency is okay.

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Commit messages:
 - Initial commit

Changes: https://git.openjdk.org/skara/pull/1677/files
  Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1677&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-2327
  Stats: 4 lines in 2 files changed: 4 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/skara/pull/1677.diff
  Fetch: git fetch https://git.openjdk.org/skara.git pull/1677/head:pull/1677

PR: https://git.openjdk.org/skara/pull/1677