Bug in loc raised for numeric label even when label is in Index
- [x] closes #26491
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

Additionally checking for the label inside values, this fixes the problem.
thanks @phofl very nice