TST: adds test for .loc on multiindex for series GH43908 (#44035)
TST: adds test for .loc on multiindex for series GH43908 (#44035)

* TST: adds test for .loc on multiindex for series GH43908

* TST: refactors test_multindex_series_loc_with_tuple_label
datapythonista/pandas,pandas-dev/pandas,pandas-dev/pandas,datapythonista/pandas,jorisvandenbossche/pandas,datapythonista/pandas,jorisvandenbossche/pandas,jorisvandenbossche/pandas,pandas-dev/pandas,pandas-dev/pandas,datapythonista/pandas,jorisvandenbossche/pandas