REGR: ExcelWriter fails when passed kwargs
- [x] closes #42286
- [x] tests added / passed
- [x] Ensure all linting tests pass, see [here](https://pandas.pydata.org/pandas-docs/dev/development/contributing.html#code-standards) for how to run them

Seeing some open resource test failure in excel writer, but not sure why. Checking if they occur on CI too.

Before this PR, I didn't notice that only xlsxwriter actually utilizes the kwargs/engine_kwargs. This makes the non-xlsxwriter tests slightly awkward - we pass the kwargs and just make sure the call to ExcelWriter doesn't fail because I don't see anything else to check.