Remove namespaces that have visibility levels are restricted from dropdown when creating a new project

What is the problem we are trying to solve?

If you have Private checked under the Restricted visibility levels field in the admin area then non-admins can not create projects in private groups.

Proposal to solve this problem

When Private is checked under the Restricted visibility levels setting private groups should not be shown to non-admins in the namespace selector on /projects/new because a non-admin cannot create projects in a private group.

Engineering implementation plan

• Update app/finders/groups/accepting_project_transfers_finder.rb#L4 to account for the Restricted visibility levels setting