fixes #22085 (int type pandas.series.index contains float type key bug)
- [x] closes #22085 
- [ ] tests added / passed
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry
checks for type using is_float, is_integer_dtype and if key is a float that does not resolve to an equivalent int and Index is int, returns false. 