Fix region aware placement policy disk weight dose not update.

[dragonls]

Motivation

We are using region aware policy in our Pulsar cluster and enable the disk weight base placement feature.

ensemblePlacementPolicy=org.apache.bookkeeper.client.RegionAwareEnsemblePlacementPolicy
bookkeeperDiskWeightBasedPlacementEnabled=false

There are different CVMs with different free disk space in a region, but we found that the traffic still seems to be balanced and is not distributed according to the weight of the free disk space.

The root cause of this case is that the disk weight information actually used to allocate bookies in RegionAwareEnsemblePlacementPolicy has not been updated at all.

The RegionAwareEnsemblePlacementPolicy actually choose bookies for ensemble by RackawareEnsemblePlacementPolicy of each region in perRegionPlacement, see org.apache.bookkeeper.client.RegionAwareEnsemblePlacementPolicy#newEnsemble. RegionAwareEnsemblePlacementPolicy.updateBookieInfo dose not update the bookieInfoMap in RackawareEnsemblePlacementPolicy of each region in perRegionPlacement, which results that the disk weight information actually used to allocate bookies in RegionAwareEnsemblePlacementPolicy has not been updated at all.

Changes

1. Overwrites the updateBookieInfo in RegionAwareEnsemblePlacementPolicy, update the bookie info in RackawareEnsemblePlacementPolicy of each region in perRegionPlacement.
2. Add test cases org.apache.bookkeeper.client.TestRegionAwareEnsemblePlacementPolicy#testRegionsWithDifferentDiskWeight.