FS2CS should use CapacitySchedulerConfiguration in FSQueueConverterBuilder

org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.converter.FSQueueConverter and its builder stores the variable capacitySchedulerConfig as a simple Configuration object instead of CapacitySchedulerConfiguration. This is misleading, as capacitySchedulerConfig suggests that it is indeed a CapacitySchedulerConfiguration and it loses access to the convenience methods to check for various properties. Because of this every time a property getter is changed FS2CS should be checked if it reimplemented the same, otherwise there might be behaviour differences or even bugs.