AffinityPlacementPlugin should utilize the size of new replicas when making placements

The AffinityPlacementPlugin has logic to make sure that nodes are not loaded up with more indexes than they can handle. It does this by filtering out nodes in the selection process that have less free disk space than the minimalFreeDiskGB configured.

However it doesn't take into account the size of the replicas it will create when doing this. So if the minimalFreeDiskGB is 30 GB, and the free disk space on a node is 50G, and a new replica's shard's leader uses 40GB for its index, then the plugin will happily choose this node, even though its likely that the node's free disk space will be 10GB after the replica is created, which is much smaller than the configured minimalFreeDiskGB.

This information should also be used when sorting on prioritizedFreeDiskGB.