fixing pep8

Author: tegardp

pandas/tests/reshape/concat/test_concat.py

@@ -652,4 +652,4 @@ def test_concat_posargs_deprecation(all_parsers):
     with tm.assert_produces_warning(FutureWarning, match=msg):
         result = concat([df, df2], " ")
     expected = DataFrame([[1, 2, 3], [4, 5, 6]], index=["a", "b"])
-    tm.assert_frame_equal(result, expected)
+    tm.assert_frame_equal(result, expected)