[FEA] Add `row_group_size` param to `to_parquet()` method

[rnyak]

Is your feature request related to a problem? Please describe.

row_group_size would be a useful argument to be added to to_parquet() method when we save processed files from NVT workflow to disk. This way, users can set row_group_size properly, and this will help prevent OOM issues when training models.

Additional context Related to https://github.com/NVIDIA-Merlin/models/issues/441.