Increase visibility of incremental rollouts in deploy boards

Description

When incremental rollouts (https://gitlab.com/gitlab-org/gitlab-ee/issues/5415) are used, people should be able to follow the progress of the rollout in the deploy boards, in a similar way we now have for standard deployments and canaries.

Incremental rollouts are already displayed in deploy boards with dots (like canary pods), but we can improve the UX even more.

Proposal

Show information about the status of the incremental rollout in the deploy board, and show "new" pods in a different style so they can be easily recognized. Something similar to what we have for canaries.

Designs

The new pods in the default state:

• Background-color: #E4F0FB
• Border: 1px in #1F78D1

The new pods in the hover state:

• Background-color: #73AFEA
• Border: 1px in #1F78D1-

"New" pods - default	"New" pod - hover