docs: fix typo 'AuoQuant' → 'AutoQuant' and clarify FINEGRAINED_FP8 library column (#44131)
Two small fixes in docs/source/en/quantization/overview.md:
1. Typo: 'AuoQuant Notebook' → 'AutoQuant Notebook' in the User-Friendly
Quantization Tools section. The link text was missing the letter 't'.
2. The FINEGRAINED_FP8 row in the comparison table had an empty 'Link to
library' cell. Since Fine-grained FP8 is implemented natively within
Transformers (no external library required), the cell now says 'Built-in'
to make it clear this is not an omission.
Co-authored-by: Maxime Grenu <maxime.grenu@gmail.com>