Private repositories / groups are always accessible for admin users

Summary

Private repositories or groups are accessible for admin users in although one is not in the admin menu. E.g. on explore groups / projects the admin can see and enter every groups / projects. And especially it is not so easy to see if a project is private (except for that small lock icon, which is hardly recognizable.

Steps to reproduce

Click on explore groups or explore projects as admin user and look through the list.

Example Project

I am very sure, that there are enough of private repositories.

What is the current bug behaviour?

Every admin user can see and access any repository also private ones in normal view.

What is the expected correct behaviour?

The full list of repositories and groups is only accessible via the admin view. Also a private repository should be marked better as private, than with that small lock icon. E.g. with red background colour.