TST:  add missing loc label indexing test
- [ ] closes #xxxx
- [x] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

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

* In the file [`pandas/tests/indexing/test_loc.py`](https://github.com/pandas-dev/pandas/blob/0a25025f37ef4e8ae8c60c4e4ca2db07ef1bc83d/pandas/tests/indexing/test_loc.py):

> [Line 66:1](https://github.com/pandas-dev/pandas/blob/0a25025f37ef4e8ae8c60c4e4ca2db07ef1bc83d/pandas/tests/indexing/test_loc.py#L66): [W293](https://duckduckgo.com/?q=pep8%20W293) blank line contains whitespace

 sure, there are some linting issues