Update pysbd_as_spacy_component.py

[guebeln0]

Thanks for a great sentence splitting package. A small contribution, after troubleshooting, why the code was not working out of the box. The spacy v3 requires a string in the add_pipe() call. The component need to be declared using the language decorator. See also https://spacy.io/usage/processing-pipelines#custom-components. Hope it helps other users.