RFR: 1393: PR bot fails on missing .jcheck/conf

[Zhao Song]

SKARA-1393 describes a problem related with `.jcheck/conf` missing.

In this patch, when the problem happens, the author of this pull request will get instructions about how to solve this problem.

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Commit messages:
 - changed the test
 - fix some typos
 - modified some logic and changed the test
 - delete an useless import
 - SKARA-1393

Changes: https://git.openjdk.org/skara/pull/1407/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1407&range=00
  Issue: https://bugs.openjdk.org/browse/SKARA-1393
  Stats: 66 lines in 2 files changed: 66 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/skara/pull/1407.diff
  Fetch: git fetch https://git.openjdk.org/skara pull/1407/head:pull/1407

PR: https://git.openjdk.org/skara/pull/1407