QA: Add a scenario for adding a deploy key

What does this MR do?

Add a scenario for adding a deploy key

Are there points in the code the reviewer needs to double check?

This took me so much more time than I thought. I feel I was kind of lost about how to organize my code. Did I make it right? How do I test this? Hit the manual action to build the package?

Does this MR meet the acceptance criteria?

• Review
  • Has been reviewed by Backend

What are the relevant issue numbers?

First step for gitlab-qa#90 (closed)