Feature Request API add support for DORA metrics

[kempy007]

As a: [site-reliability/devops/software] engineer,
I want: to display these metrics in a pane of glass of my orgs choice,
so that: we can consolidate our data into one pane of glass.

• Feature Documentation: https://cloud.google.com/blog/products/devops-sre/using-the-four-keys-to-measure-your-devops-performance
• API Documentation: https://docs.gitlab.com/ee/api/dora/metrics.html