Reuse the connection pool.
Create redis_master to reuse its connection pool
Unit Tests for RateLimit
Unit Tests for RateLimit

Only testing app, as the RateLimit check is always run before the API call
itself (it is a decorator). Thus, it applies to App, Category, Task and TaskRuns.
Add RateLimit to API calls
Use the RedisMaster node
Refactor RateLimit tests to its own Class