No mongo cache in DatasetRemovalPlan
don't keep the full query result in memory (as mongoengine does by default)

this should reduce the frequency of memory spikes and could have an effect of the memory issues we're having
No mongo cache in DatasetRemovalPlan: don't keep the full query result in memory (as mongoengine does by default)

this should reduce the frequency of memory spikes and could have an effect of the memory issues we're having