Add Civo to the create cluster page

Release notes

Problem to solve

As a Civo + GitLab user, I would like to start a new Civo Kubernetes cluster directly from the GitLab UI.

Proposal

Civo already contributed the required documentation and example project to create a Civo cluster with Terraform that connects to GitLab with the agent.

We should add a button with the Civo logo to the cluster creation page. The button should link to the documentation: https://docs.gitlab.com/ee/user/clusters/create/

The Civo brand assets can be found here https://www.civo.com/brand-assets

Feature Usage Metrics

• button click events
• pageviews of https://docs.gitlab.com/ee/user/infrastructure/clusters/connect/new_civo_cluster.html