Add a test for User#ci_authorized_runners
What does this MR do?
Add a test for User#ci_authorized_runners
Are there points in the code the reviewer needs to double check?
Should we add Project#add_user
so that it's similar to Group#add_user
?
Why was this MR needed?
I am going to make some changes to this method for !4093 (merged), but I couldn't find a corresponding test so I want to add it in case I would break anything.
What are the relevant issue numbers?
This is a test for current behaviour, before implementing #3407 (closed)