DOC: Validating that the word pandas is correctly capitalized
- [x] closes #32316 
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

As suggested by @datapythonista , I've added checks in `ci/code_checks.sh` to look if the `pandas` is being referenced in a standardized way i.e `pandas`,  not ` *pandas* `  or  `Pandas`

@datapythonista I've only added checks to see if pandas is being referenced correctly, but not showing where it's changed or how many references are wrong. 
Should I add checks for that also ? What do you think ?