Fixed PEP8 whitespace issue

Author: cbertinato

pandas/tests/indexes/datetimes/test_ops.py

@@ -175,7 +175,7 @@ def test_round_ops(self, test_input, rounder, freq, expected):
             result = func(freq)
             expect = pd.DatetimeIndex([expected], tz=tz)
             tm.assert_index_equal(result, expect)
-            
+
     def test_round_daily(self):
         dti = pd.date_range('20130101 09:10:11', periods=5)
         result = dti.round('D')