Code Insights: Add tests for dashboard and insight ownership transferring flow
Created by: vovakulikov
Part of https://github.com/sourcegraph/sourcegraph/issues/24232
Context
Since #22748 PR we have dashboard ownership levels functionality. In a nutshell, this means that your insight
- can be included in all your dashboards if that insight is stored in the global setting subject (global scope)
- can be included only in one org level dashboards and in your personal dashboards
- can be included only in your personal dashboards if that insight has a personal visibility level
This PR adds some unit test to test this logic.