RFR: 1393: PR bot fails on missing .jcheck/conf [v4]

[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.

Zhao Song has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains two commits:

 - Merge branch 'master' into SKARA-1393
   
   # Conflicts:
   #	bots/pr/src/test/java/org/openjdk/skara/bots/pr/CheckTests.java
 - need import network

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Changes: https://git.openjdk.org/skara/pull/1407/files
 Webrev: https://webrevs.openjdk.org/?repo=skara&pr=1407&range=03
  Stats: 393 lines in 6 files changed: 347 ins; 12 del; 34 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