add test to check crosstab supports Float64 formats
- [x] closes #50313
- [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).

A  new test is added. The test validates `crosstab` behavior with `Float64`. I have checked that the problem occurs when `Float64` is used together with `margins=True`. 
The test fails on `1.5.2` and passes on `main`.
thx @natmokval  Thank you, @phofl, for reviewing my PR.