Hide public build setting on private repo

What does this MR do?

Ensure that private projects have private builds.

1. Pre-existing private projects will have their builds made private
2. Selecting a visibility level of Private will disable and un-check the Public Build checkbox

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

1. Will updating existing private projects to have private builds cause upgrade issues?
2. Are there any other screens that need updated?

Why was this MR needed?

Anonymous users can view builds when Public Builds is checked. When a project has PRIVATE visibility, anonymous users cannot see the project. Nor should they be able to see the builds.

What are the relevant issue numbers?

#13289 (closed)

Screenshots (if relevant)