Remove xfail in test_usecols_basic

Author: rhshadrach

pandas/tests/io/parser/usecols/test_usecols_basic.py

@@ -7,8 +7,6 @@
 import numpy as np
 import pytest
 
-from pandas._config import using_string_dtype
-
 from pandas.errors import ParserError
 
 from pandas import (
@@ -547,7 +545,6 @@ def test_usecols_additional_columns_integer_columns(all_parsers):
     tm.assert_frame_equal(result, expected)
 
 
-@pytest.mark.xfail(using_string_dtype(), reason="TODO(infer_string)")
 def test_usecols_dtype(all_parsers):
     parser = all_parsers
     data = """