Shields has long had an in-memory cache with some complex logic for determining when the cached values are used and when they are flushed. At the time this was implemented, squeezing cache performance was helpful since there was no downstream cache. For years now we've used Cloudflare as a CDN, so trying to cache onboard is less useful than before. Furthermore, since the cache is very small and only used in fairly restrictive ways, it probably has very little impact on performance.
* which --> variant
* which --> alias
* which --> format
* improve param names in codeclimate
* improve param names in github-issue-detail
* update github-issue-detail unit tests
Continue to implement #2698:
- Add `core/base-service/index.js` (but hold off on moving the things it imports)
- Add shortcuts in `services/index.js` for Base*Service, errors, and deprecatedService. This file will be streamlined later to avoid cluttering it with rarely used bits.
- Apply consistent ordering of imports and use of `module.exports` in testers.
- Remove some renaming of imports.
- Remove obsolete tests here and there.
