possible division by zero in DynamicDiffusive load balancer
If a block has no outflow division by zero may occur here: https://i10git.cs.fau.de/walberla/walberla/blob/master/src/blockforest/loadbalancing/DynamicDiffusive.h#L344
If a block has no outflow division by zero may occur here: https://i10git.cs.fau.de/walberla/walberla/blob/master/src/blockforest/loadbalancing/DynamicDiffusive.h#L344