Change rate limit for issues creation to be disabled by default

Follow-up issue to address discussion:

There seems to be an inconsistent approach to rate limit defaults. For the main ones they're not activated by default but for specific ones like this and Raw files there is a default applied. It may be better for customers (self managed) if these were consistently set to off? My small concern being that customers won't be aware of active limits until they hit them and each environment would have different limits typically.

Edited Jul 06, 2020 by Eugenia Grieff