UnicodeEncodeError - Several Different PDFs

[nickrallison]

Bug

Docling parses some pdfs successfully but fails to write the markdown file with the results.
UnicodeEncodeError: 'charmap' codec can't encode character '\u2217' in position 51: character maps to <undefined>

I was able to resolve this for this specific PDF by changing line 1941 in this file under docling_core\types\doc\document.py but the tests failed

Steps to reproduce

1. Download this pdf: https://typeset.io/pdf/computational-challenges-in-bounded-model-checking-44b7toabj9.pdf
2. docling computational-challenges-in-bounded-model-checking-44b7toabj9.pdf

I've encountered this on other PDFs as well:
https://batch.libretexts.org/print/url=https://math.libretexts.org/Bookshelves/Combinatorics_and_Discrete_Mathematics/Elementary_Foundations%3A_An_Introduction_to_Topics_in_Discrete_Mathematics_(Sylvestre)/03%3A_Boolean_algebra/3.02%3A_Disjunctive_Normal_Form.pdf

Docling version

Docling version: 2.12.0
Docling Core version: 2.9.0
Docling IBM Models version: 3.1.0
Docling Parse version: 3.0.0

Python version

Python 3.11.9

[maxmnemonic]

@nickrallison thanks for pointing this out!
I'll test it more, and if it's not breaking anything (which I think it shouldn't) we'll regenerate tests.