fix: "MOVED" err not crashing process when slot was not assigned
fix: "MOVED" err not crashing process when slot was not assigned

If slot was not previously discovered by ioredis - it would cause a crash as it
would try to rewrite a masterNode on a missing object

DynamicYield/ioredis,luin/ioredis,luin/ioredis,DynamicYield/ioredis,luin/ioredis