Automatically request new review when state changed to "awaiting change review"

[brettcannon]

Now that GitHub has the concept of a "review request", we could take advantage of that when Bedevere is triggered to message people requesting changes by requesting reviews again from those people. That way we get both the label to tell people when viewing their https://github.com/pulls/review-requested page, but also any other part of the GitHub UI which renders review states.

[lysnikolaou]

Would it maybe make sense to wait until the warning on the Review Requests API page gets out of the way?

Warning: The API may change without advance notice during the preview period. Preview features are not supported for production use. If you experience any issues, contact GitHub Support.

[brettcannon]

@lysnikolaou it depends on whether that warning applies to just the emoji support or the API all-up. Plus I didn't want to forget the idea so I opened this issue regardless.

[lysnikolaou]

You are right, @brettcannon. After some digging, I found out that the API itself is not in beta, so it must be ready to use in production. I'll try to have a PR ready in the next days.

[lysnikolaou]

Since #168 is now merged, I think this can be closed.

[brettcannon]

@lysnikolaou you're right. :)