Build LSIF dumps on HEAD of pull request, not merge commit
Created by: mrnugget
See Slack thread here: https://sourcegraph.slack.com/archives/C07KZF47K/p1639482287186000
Created by: mrnugget
See Slack thread here: https://sourcegraph.slack.com/archives/C07KZF47K/p1639482287186000