Fix minor problems in punctuation and capitalization model
1. Fix creating tarred dataset for cases when tokenizer name contains `/` character, e.g. `'facebook/mbart-large-50'`.
2. Fix subclass check [here](https://github.com/NVIDIA/NeMo/blob/f83b2c5524a787be21ffea170850c4b5486eac2b/nemo/collections/nlp/data/token_classification/punctuation_capitalization_tarred_dataset.py#L383). It did not work if `error_class_or_function` is not a class
3. Fix return typing in a [method](https://github.com/NVIDIA/NeMo/blob/f83b2c5524a787be21ffea170850c4b5486eac2b/nemo/collections/nlp/data/token_classification/punctuation_capitalization_dataset.py#L436) `TokenizeCreateMasksClipWorker.__call__()`.
4. Make comment [here](https://github.com/NVIDIA/NeMo/blob/f83b2c5524a787be21ffea170850c4b5486eac2b/nemo/collections/nlp/data/token_classification/punctuation_capitalization_dataset.py#L67) more comprehensible. Before fix it was identical to a name of a model config section `common_dataset_parameters`, whereas it was not related to the section in any way.
5. In a spirit of fix 1 add checking of characters in `tar_file_prefix` parameter in functions [`create_tarred_dataset()`](https://github.com/NVIDIA/NeMo/blob/f83b2c5524a787be21ffea170850c4b5486eac2b/nemo/collections/nlp/data/token_classification/punctuation_capitalization_tarred_dataset.py#L633) and [`get_args()`](https://github.com/NVIDIA/NeMo/blob/f83b2c5524a787be21ffea170850c4b5486eac2b/examples/nlp/token_classification/data/create_punctuation_capitalization_tarred_dataset.py#L64).