Use queue's available_resources when autoscaling

[ryanhamel]

The integration currently only considers the MaxCoreCount set in the nodearray to limit autoscaling. PBS has limits at a queue level that we are not considering. We are already parsing and storing this, in PBSQueue.resource_state.available_resources, we just need to propagate that as a limit to the jobs.

Excellent internal write up - see Ava ticket 2406060060001613