BUG: Respect check_dtype in assert_series_equal
- [x] closes #32747
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`

I'm not sure if https://github.com/pandas-dev/pandas/blob/master/pandas/_testing.py#L1174 needs to change too?

cc @jorisvandenbossche 
Hello @dsaxton! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:







There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2020-03-17 18:01:47 UTC can you add a whatsnew note (can put in bug fixes other section) > can you add a whatsnew note (can put in bug fixes other section)

IIUC the bug is only on master, not released. Is the whatsnew needed? > IIUC the bug is only on master, not released. Is the whatsnew needed?

Part of the fix did fix something compared to 1.0 (eg for intervals) Thanks @dsaxton ! > Part of the fix did fix something compared to 1.0 (eg for intervals)

If this fixes something that worked in 1.0, then should this be backported? Sorry, I meant: it's partly fixing a bug that is in 1.0 (hence the whatsnew note is fine), and partly a regression that is only in master (which doesn't need a whatsnew). 
But the bug from 1.0 is not a regression nor critical, so shouldn't need a backport ah. my bad.