Create a consistent way to manage configuration settings

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Close this issue

Application settings can be handled in a number of different ways, from settings within the application itself, application settings configured through the API as well as with feature flags, this makes it difficult to know where to look when settings need to be changed.

This was experienced during gitlab-com/gl-infra/production#3875 (closed) where 'automatic_purchased_storage_allocation' was available as a feature flag as well as an API configuration making it unclear which should be used.

In order to maintain GitLab.com's availability, SREs, and ideally, anyone should be able to quickly find and change settings in a consistent way.