Create a new endpoint to copy common_metrics.yml to the local project

As part of #34779 (closed) the user should be able to create a new dashboard form a system one, such as common_metrics.

Goal

We would like for the users to be able to create "clone" the common_metrics.yml dashboard so they can edit it and adapt it to their needs.

Proposal

Add a new backend endpoint which takes a path to "system" dashboard (e.g. config/prometheus/common_metrics.yml) and adds it to the repository.

Input

• project path, possibly already in the path of the endpoint.
• dashboard, filepath of the "system" dashboard config/prometheus/common_metrics.yml
• file name: Name of the new .yml file my_dashboard.yml
• possibly commit message?
• possibly use POST method?

Output

200 (201 created?) after the file has been created

• file name so the knows where to load the newly created dashboard to.