BUG: Retain timezone dtype with cut and qcut
- [x] closes #19872
- [x] tests added / passed
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

Timezone dtypes were getting lost as the `_preprocess_for_cut` function called `np.asarray` on all incomming data. I added an additional check that the input array is 1D as stated in the docs of `cut` and `qcut`. 