RFR: 1706: Store github checks in PR unique way [v2]

[Zhao Song]

> Currently, checks in GitHub are stored in the commit. So if multiple PRs share the same source commit, then they will compete with the check-runs and store their different checksum in there. This in turn means that all, or most of those PRs will always think the check is outdated when a CheckRun is performed next.
>  
> This patch adds repository name and pull request id to the name of check in Github. Therefore, even if multiple PRs share the same source commit, every PR will store a unique check in the commit and there is no competition exists.

Zhao Song has updated the pull request incrementally with one additional commit since the last revision:

  fix problems

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

Changes:
  - all: https://git.openjdk.org/skara/pull/1470/files
  - new: https://git.openjdk.org/skara/pull/1470/files/df2fc3c1..c7909f03

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=skara&pr=1470&range=01
 - incr: https://webrevs.openjdk.org/?repo=skara&pr=1470&range=00-01

  Stats: 11 lines in 4 files changed: 4 ins; 3 del; 4 mod
  Patch: https://git.openjdk.org/skara/pull/1470.diff
  Fetch: git fetch https://git.openjdk.org/skara pull/1470/head:pull/1470

PR: https://git.openjdk.org/skara/pull/1470