CI: added unwanted pattern test case for "foo.__class__" instead of type(foo)
- [ ] closes #xxxx
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

ref #29816 (splitted to #29889, #29893, #29894, #29902, #29904, #29905)
Looks good. To be sure can you intentionally change the code somewhere to make this fail so we can see how it looks in CI? ping @WillAyd  ![image](https://user-images.githubusercontent.com/16733618/69904819-6008ae00-13a3-11ea-9e33-29411d0d4a93.png)

This is how it looks in CI. Might be worth adding something that explains one should use type()? Great thanks @MomIsBestFriend 