Global Partition Resolver is ignored

[sebestenyb]

1. The BalancedDispatchable contains a base method of getPartitionKey()
2. The BalancedRedisQueue prioritise this method to resolve the partition in its resolvePartition method over the partitionResolver callback
3. Since every balanced job uses the BalancedDispatchable trait, every job implements the getPartitionKey, the global partition resolver is ignored.

I think the trait should not implement the getPartitionKey method, leaving it to the actual jobs, and the property checks should maybe be moved to the BalancedRedisQueue@resolvePartition(), before the method checks.

[YanGusik]

Thanks for reporting! I've left feedback on the PR #7 with a suggested fix for the check order. See #7 (comment)

[sebestenyb]

Ah true, you are right.
Unfortunately the BalancedDispatchableTest were failing, as they were testing the getPartitionKey method on the trait I removed, I changed that to use reflection on the BalancedRedisQueue.

I also had to change the visibility of the $partitionKey property of the BalancedDispatchable to public, as now we access it externally.