RFR: cli: add --ignore flag to git-sync

[Robin Westberg]

On Wed, 21 Oct 2020 18:13:27 GMT, Erik Helin <ehelin at openjdk.org> wrote:

> Hi all,
> 
> please review this patch that adds the `--ignore` flag to `git-sync`. The `--ignore` flag is a regular expression for branches that should *not* be synced. The default value for `--ignore` is `pr/.*` to avoid sync branches created by Skara to facilitate pull requests with dependencies.
> 
> Testing:
> - [x] Manual testing 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/907