Correct pytest raises

Author: radekbenesinno

pandas/tests/io/test_pytables.py

@@ -1229,7 +1229,8 @@ def test_read_missing_key_close_store(self):
             df = pd.DataFrame({'a': range(2), 'b': range(2)})
             df.to_hdf(path, 'k1')
 
-            pytest.raises(KeyError, pd.read_hdf, path, 'k2')
+            with pytest.raises(KeyError):
+                pd.read_hdf(path, 'k2')
 
             df.to_hdf(path, 'k2')