DOC: fix EX03 errors in docstrings
- [ ] xref #56804 
- [ ] [Tests added and passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#writing-tests) if fixing a bug or adding a new feature
- [x] All [code checks passed](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#pre-commit).
- [ ] Added [type annotations](https://pandas.pydata.org/pandas-docs/dev/development/contributing_codebase.html#type-hints) to new arguments/methods/functions.
- [ ] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.

hi @mroeschke, I rebased and resolved the conflict but then noticed from https://github.com/pandas-dev/pandas/pull/56863 that `ruff` can autofix all these errors. Let me know if I should close this MR in favor of https://github.com/pandas-dev/pandas/pull/56863 It's OK to still work on this PR. While the ruff PR may also reformat this docstring in the future, it is still appreciated to have your contribution in this PR. @mroeschke this PR is ready for review. I was about to expand it a bit but then noticed that `pd.MultiIndex` is already removed in [this PR](https://github.com/pandas-dev/pandas/pull/56880/files#diff-ddd4b0b4b985cabe7be60218e66a87d5b92e977a009d6c22bfa770572a2046b8L93) while the docstring is not fixed yet (The pipeline indeed raised an error [here](https://github.com/pandas-dev/pandas/actions/runs/7525838093) and also [here](https://github.com/pandas-dev/pandas/actions/runs/7532519414/job/20503312629) on `main` but the pipeline is still green!). 

I think we can merge this PR first to heal `main`? It's not the first error there too.

![image](https://github.com/pandas-dev/pandas/assets/25203655/2a845878-6e60-4b9f-b4f3-1deade290c5e)
 I managed to reproduce the error [here](https://github.com/pandas-dev/pandas/actions/runs/7534583802/job/20509194445?pr=56897). Will go ahead and fix all the current bugs on `main`