RFR: Ensure that the pr head is present locally when pushing a dependency branch

[Erik Helin]

On Mon, 26 Oct 2020 11:20:04 GMT, Robin Westberg <rwestberg at openjdk.org> wrote:

> When the pull request branch notifier creates a dependency target branch, we need to ensure that the head commit is actually present locally.

Looks good!

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

Marked as reviewed by ehelin (Reviewer).

PR: https://git.openjdk.java.net/skara/pull/918