Better Deploy Keys page

Description

The current Deploy Keys page (/<project-name>/deploys_keys)

• does not have a great empty state
• does not list deploys keys elegantly (information seems to float on the line).

We need to enhance it.

UX Proposal

Empty state

Redesign the list of deploy keys

Reference

• Part of meta issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/22171