Added complexity rule for api query methods [warn]
Added complexity rule for api query methods [warn]

- We want to keep behaviour in services and libraries, not in API endpoints
- This rule runs complexity _only_ on the query methods, and has it set super low - just 3
- Methods that have higher complexity are a great indicator of places where we've left behaviour in the API, however!
- It's indicative, not definitive. At least with an eslint rule we can if needs be disable it where we decide the code is OK

janvt/Ghost,janvt/Ghost,TryGhost/Ghost,e10/Ghost,ErisDS/Ghost,e10/Ghost,TryGhost/Ghost,ErisDS/Ghost,TryGhost/Ghost,ErisDS/Ghost