DOC: Updating the docstring of read_csv and related functions
- [X] closes #23496
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

Make docstrings of the following modules to comply with [pandas docstring](https://pandas.pydata.org/pandas-docs/stable/contributing_docstring.html)

- pandas.read_table
- pandas.read_csv
- pandas.read_fwf
