As part of the work done in SERVER-57461 we realized that `singleBatch` in the find command is also a legacy concept. We want to remove `singleBatch` but we can't remove `singleBatch` unless we deprecate the use of negative limit first because drivers use `singleBatch` to implement negative limit semantics,

https://github.com/mongodb/mongo-python-driver/blob/master/pymongo/message.py#L201-L204

After we deprecate negative limit support we can remove `singleBatch`  from the find command and elsewhere in the codebase.