DOC: Update to Documentation - Grammatical Updates and Typo Corrections
Typo correction and grammatical updates on the "Pandas Documentation" page (https://pandas.pydata.org/docs/). 

Title: 
pandas documentation -> Pandas Documentation
Capitalization of title.

The text below "Useful links":
The word "pandas" is not capitalized. Since it is the first word of a sentence, it must be capitalized. 
Grammatical update to the whole sentence. 

No links were changed.

Before changes:
![before](https://github.com/pandas-dev/pandas/assets/88173271/2cab605e-4e5d-4cbc-b8fb-5cac049d4f90)

After Changes:
![after](https://github.com/pandas-dev/pandas/assets/88173271/80e08d14-cce2-4000-9ec3-6555b66f6063)
Thanks but the lowercasing is intentional. See https://pandas.pydata.org/about/citing.html Would it be possible for me to send another PR without any capitalized words?  IMO the sentence you edited is fine as is, but happy to have contributions towards issues labeled `good first issue` 