Add batched decorator

[ryantwolf]

Refactors batched to be in a decorator. This frees the user from having to be knowledgable about how the underlying DocumentFilter or DocumentModifier when initializing ScoreFilter or Modify respectively.

Unit tests pass. The following scripts were manually tested and work properly.

examples/classifier_filtering.py
examples/find_pii_and_deidentify.py
nemo_curator/scripts/find_pii_and_deidentify.py
tutorials/tinystories/main.py

The examples and other scripts have been manually tested to work.