RFR: 2286: Git jcheck --working-tree/--staged not compatible with some checks

[Zhao Song]

In [SKARA-1690](https://bugs.openjdk.org/browse/SKARA-1690), I tried to make jcheck cli able to run jcheck on the diff in current working tree. But seems like this feature is not compatible with some jchecks like problemLists check.

When jcheck is checking staged or working-tree, I think there is no point to run some checks that require real commit message. Therefore I disabled the checks and Skara CLI will print a prompt to user.

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Commit messages:
 - update
 - update
 - SKARA-2286

Changes: https://git.openjdk.org/skara/pull/1658/files
  Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1658&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-2286
  Stats: 16 lines in 3 files changed: 13 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/skara/pull/1658.diff
  Fetch: git fetch https://git.openjdk.org/skara.git pull/1658/head:pull/1658

PR: https://git.openjdk.org/skara/pull/1658