RFR: pr: separate commit and pr commands

[Robin Westberg]

On Thu, 25 Feb 2021 09:53:33 GMT, Erik Helin <ehelin at openjdk.org> wrote:

> Hi all,
> 
> please review this pull request that properly separates pull request and commit commands at the source code level. The class `CommandWorkItem` is renamed to `PullRequestCommandWorkItem` and then I did a number of smaller follow-out refactorings from this renaming.
> 
> Testing:
> - [x] `make test` passes on Linux x64
> 
> Thanks,
> Erik

Looks good!

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Marked as reviewed by rwestberg (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/1038