Allow admins to list all external remote repositories mirrored in Gitlab via an Admin view
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### Problem to solve
Development teams are mirroring to Gitlab several projects externally (ie GitHub, Bitbucket, ...) thanks to the [repository mirroring feature](https://docs.gitlab.com/ee/user/project/repository/repository_mirroring.html). In order to get more control on an increasing list of mirrors, particularly for security/legal reasons but also to have an overview of these mirrors, we should have a dashboard (a mirrors view in the admin panel) showing all (pull and push) remotely mirrored upstreams of a GitLab instance (ie filterable by internal or external) and their information. Having it natively implemented in Gitlab would be much more convenient (especially for large instances with very many projects).
| | user story |
| ------ | ------ |
| who | as a Systems Administrator, |
| what | I want to get the list of all project mirrored with GitHub |
| why | so I can check easily/quickly if some sensitive data are exposed |
<!-- What problem do we solve? Try to define the who/what/why of the opportunity as a user story. For example, "As a (who), I want (what), so I can (why/value)." -->
### Intended users
* [Cameron (Compliance Manager)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#cameron-compliance-manager)
* [Sidney (Systems Administrator)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sidney-systems-administrator)
* [Sam (Security Analyst)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sam-security-analyst)
* [Alex (Security Operations Engineer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#alex-security-operations-engineer)
### Proposal
A "Mirrors" view in the admin panel showing all mirrors for a GitLab instance.
* Columns (should be sortable and filterable)
* project name + URL as a link: `[project name](url)`
* mirrors' list
* a "sub" table with mirrors details
| Project | Mirror(s) |
| --------------------- | ------------------------------------------------------------------ |
| `[project name](url)` | <ul><li>`mirror 1`</li><li>`mirror 2`</li><li>`mirror 2`</li></ul> |
| `[project name](url)` | <ul><li>`mirror 1`</li></ul> |
| `[project name](url)` | <ul><li>`mirror 1`</li><li>`mirror 2`</li> |
<!-- How are we going to solve the problem? Try to include the user journey! https://about.gitlab.com/handbook/journeys/#user-journey -->
### Availability & Testing
:construction:
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What risks does this change pose to our availability? How might it affect the quality of the product? What additional test coverage or changes to tests will be needed? Will it require cross-browser testing?
Please list the test areas (unit, integration and end-to-end) that needs to be added or updated to ensure that this feature will work as intended. Please use the list below as guidance.
* Unit test changes
* Integration test changes
* End-to-end test change
See the test engineering planning process and reach out to your counterpart Software Engineer in Test for assistance: https://about.gitlab.com/handbook/engineering/quality/test-engineering/#test-planning -->
### What is the type of buyer?
* [Skyler - the Chief Information Security Officer](https://about.gitlab.com/handbook/marketing/strategic-marketing/roles-personas/buyer-persona/#skyler---the-chief-information-security-officer)
* ~"GitLab Premium"
issue