Add API functions to work with artifacts

[ligurio]

Github Actions API have endpoints to list, get and delete artifacts -
https://docs.github.com/en/free-pro-team@latest/rest/reference/actions#get-an-artifact

Is it possible to implement them in Golang SDK for GH Actions?

[github-actions]

This issue is stale because it has been open for 14 days with no
activity. It will automatically close after 7 more days of inactivity.

[github-actions]

This issue has been automatically locked since there has not been any
recent activity after it was closed. Please open a new issue for
related bugs.