Show pipeline minigraph on Ops Dashboard

We wanted to show the pipeline minigraph on the Ops Dashboard, but we didn't have time to fully implement this within a single release. (See https://gitlab.com/gitlab-org/gitlab-ee/issues/5781#note_101056335)

We should add this to the dashboard, as it is an important component of the project's health. We have a open spot for it on the card right now:

image

We should show the current pipeline on master, with the time since it was completed shown below. (If it is finished) This would allow users to:

  1. Understand if the pipeline succeeded, failed, or is running
  2. When the pipeline was last executed, and therefore the last deploy.