Ensure all Grape APIs parameters have desc defined

Overview

To ensure consistency across our Grape API definitions, we should ensure that there is a set of fields defined for every single endpoint. This will ensure that generated OpenAPI documentation is clear and consistent.

Currently, there are 422 examples of parameters with no desc field, although some do have description. We should enforce all parameters having a desc field to use when generating documentation

Implementation plan

• Add a new rubocop which checks all API endpoints for a desc field for every API endpoint parameter.
• For all instances where this cop fails, either add a detail field (where its content is obvious), or create an issue for the product team in question to add it.