`GITHUB_{REPOSITORY,SHA,PR}` are not propagated

[veprbl]

This prevents us from posting benchmark statuses from eicweb. Used to work before.

[wdconinc]

99c03af

[wdconinc]

We don't have a PR when we trigger on push.

[veprbl]

We don't have a PR when we trigger on push.

That is true, but the status is reported based on SHA. The PR was intended to enable image_browser to post comments.

[veprbl]

Fixed in #84