Add Health Check button to GitLab Duo Pro page

Problem to solve

We've began to introduce probes to evaluate the readiness of an instance to utilize GitLab Duo. This iteration will focus on introducing a mechanism to expose those responses in the frontend.

Proposal

• Add a new button to the GitLab Duo Pro page in the Admin area on self-managed
• Trigger the evaluation probes using the newly introduced Run health check button.
• How the results are rendered will be explored in #474860 (closed).

Current	Proposed