DOC: Add code-formatting and cross-reference links to `read_csv` docstring
State: closed

- [x] Toward #53674 (specifically for `pandas.read_csv` for now).
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).

Added code formatting where applicable and added sphinx cross-referencing tags for any `pandas` classes or functions. Also cleaned up cases where "default None" was specified rather than "optional".

Note: I plan to submit future PRs focused on editing the content (e.g., #53673) but wanted to start with the formatting changes.

Labels:
name: Docs
name: IO CSV
description: read_csv, to_csv

Comments:
```
2023-06-20T05:01:47.5693361Z /home/runner/work/pandas/pandas/pandas/io/parsers/readers.py:docstring of pandas.io.parsers.readers.read_csv:176: WARNING: Bullet list ends without a blank line; unexpected unindent.
2023-06-20T05:01:47.5694692Z /home/runner/work/pandas/pandas/pandas/io/parsers/readers.py:docstring of pandas.io.parsers.readers.read_csv:178: ERROR: Unexpected indentation.
2023-06-20T05:01:47.5695421Z /home/runner/work/pandas/pandas/pandas/io/parsers/readers.py:docstring of pandas.io.parsers.readers.read_table:176: WARNING: Bullet list ends without a blank line; unexpected unindent.
2023-06-20T05:01:47.5696750Z /home/runner/work/pandas/pandas/pandas/io/parsers/readers.py:docstring of pandas.io.parsers.readers.read_table:178: ERROR: Unexpected indentation.
```
Thanks @mroeschke for the report on this. I am trying to have a closer look but ran into issue #53788 which I need to figure out before I can rebuild the docs I think. Also, just since I'm fairly new at this, is there a simple way to locate specific lines in a docstring (i.e. 176 and 178 that are being flagged)? It's not immediately obvious given that the docstring in the source code is built out of format strings (i.e. isn't a literal) so it makes it hard to know which lines are causing trouble just from reviewing the `py` source. Thanks for the help.
Hi @mroeschke, I located the error and fixed the formatting with the `read_csv` docstring. Hopefully that will have rectified this issue.
What is the meaning of the cancelled checks? Do I need to do something to re-run or was that intentional?
Thanks @tpaxman. The canceled checks are due to some unit tests that are unrelated 
Sorry for chipping in @tpaxman. Though "pandas" is a module, IMHO it should not be enclosed in backticks here? I don't see it being considered inline code anywhere else in the docs either. (Just mentioning this because I see you making some doc contributions recently. Maybe you can make this change in one of your currently open PRs if you agree with my point).

<details>
<summary>Some other suggestions</summary>
<p></p>

1. I think lists should have spaces after the commas in `[0,1,3]`.
<img width=60% src="https://github.com/pandas-dev/pandas/assets/108576690/3c4ee662-77b6-4e4c-8a57-0f7e6aa5fada">

2. Not sure but do you think these should be considered string literals? Currently its a bit hard to tell them apart because the quotation marks in text mode is small (especially that the empty string `''` is hard to tell at first glance).
<img width=60% src="https://github.com/pandas-dev/pandas/assets/108576690/6aff10c0-ddbb-4c9d-9d69-6cb40bbe9176">

</details>
Thank you, @Charlie-XIAO! I agree with all your suggestions for sure. I was thinking about whether to convert that list of ``na_values`` to string literals and I think it would help readability. I can submit a follow up PR to address those.

As for the formatting for the pandas module, I am not totally clear on what is preferred in the docs since I've seen instances of both plain text and code-formatted versions. That might be something the maintainers could advise on. And if there is a preferred format, it would be good to have that added to the developer guide as well.