chore: Table chunking

[amanda103]

This change is adding to our add_chunking_strategy logic so that we are able to chunk Table elements' text and text_as_html params. In order to keep the functionality under the same by_title chunking strategy we have renamed the combine_under_n_chars to max_characters. It functions the same way for the combining elements under Title's, as well as specifying a chunk size (in chars) for TableChunk elements.

*renaming the variable to max_characters will also reflect the 'hard max' we will implement for large elements in followup PRs

Additionally -> some lint changes snuck in when I ran make tidy hence the minor changes in unrelated files :)

TODO:
✅ add unit tests
--> note: added where I could to unit tests! Some unit tests I just clarified that the chunking strategy was now 'by_title' because we don't have a file example that has Table elements to test the 'by_num_characters' chunking strategy
✅ update changelog

To manually test:

In [1]: filename="example-docs/example-10k.html"

In [2]: from unstructured.chunking.title import chunk_table_element

In [3]: from unstructured.partition.auto import partition

In [4]: elements = partition(filename)

# element at -2 happens to be a Table, and we'll get chunks of char size 4 here
In [5]: chunks = chunk_table_element(elements[-2], 4)

# examine text and text_as_html params
ln [6]: for c in chunks:
                    print(c.text)
                    print(c.metadata.text_as_html)

[badGarnet]

can we also have assert to check for this example that

• without combining text under n chars set to 5 there are tiny chunks
• with the setting we have text with minimum 5 chars