CI: reenable e2e tests, add video recording
Created by: chrismwendt
I disabled the e2e tests in https://github.com/sourcegraph/sourcegraph/pull/2825 due to a failure seen in https://github.com/sourcegraph/sourcegraph/issues/2822. I wasn't able to repro the problem, but this PR adds video recording so we can see what goes wrong next time.