fixed spelling errors in whatsnew, userguide, and ecosystem
Hi there, 

I fixed the spelling errors mentioned here. https://github.com/pandas-dev/pandas/issues/37252

 The 2 "wit" spelling errors were confusing, and I could not understand the sentences. 

This is my first pull request, so please excuse my ignorance if I did something incorrectly.

Thanks. 





Thanks @asharma13524 !