v5.5.6

Update connection logic to always await a test key write to ensure that the connection is ready before returning

solved #293

This made connection.connect (and therefore worker.connect and scheduler.connect) awaitable until we are really sure that we can read and write to redis.

We rely on the fact that both node-redis and ioredis will buffer and retry redis commands until they either succeed, timeout, or fail. This allows us to skip the on('connected') event and simply wait until we can read data from redis

Update all dependencies

This includes moving to standard v14 which included some large changes to the linter rules