REGR: Series.loc with a MultiIndex containing Timestamp raises InvalidIndexError
ci testing fix in https://github.com/pandas-dev/pandas/issues/35858#issuecomment-678683559

- [ ] closes #35858
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

can you add the test from the OP as well yep. the fix looks good. will add release note and tests shortly. I can't block by requesting changes on my own PR, moving to 1.1.4 so release note needs to be moved. closing for now instead. Will re-open after 1.1.3 release.

I've started the final release readiness checks. merging now would require going back to square one. @jreback  re-opened just in case this is almost ready lgtm.