Manage achievements on user profile
Add the ability to manage awarded achievements displayed on a user's profile.
As a first boring solution, let's just allow users to opt-out by ticking a box on their profile.
Problem
With the addition of GitLab Achievement (Badging/Award) System users need a way to manage what achievements they want to display on their profile to allow them to customize their profile as desired and prevent unwanted achievements from being displayed.
Proposal
Add a section to the Edit Profile -/profile to manage achievements. Achievements should be opt-in and not displayed unless a user has chosen to display them.
Add achievements section below Main settings section
Add achievements dropdown
If the maximum number (proposed 3) of achievements have been added, the add achievements dropdown should be disabled.
