BUG: Fix read_csv index dtype override
- [x] closes #59077
- [x] [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.~~
- [x] Added an entry in the latest `doc/source/whatsnew/vX.X.X.rst` file if fixing a bug or adding a new feature.
hey, thanks for the ping and the PR - I'm not really familiar with this part of the codebase. I can take a look but I'm afraid there are other priorities at the moment @mroeschke Hi Matthew, can you help take a look at my pr for this? Sorry I just merged https://github.com/pandas-dev/pandas/pull/59316 which overlaps with your fix here. Thanks for the contribution but going to close now that the issue is fixed