Migrate "test/unit/test_providers_raw_master_key.py" from unittest to pytest (#123)

* Migrating unit/test_deserialize.py from unittest from pytest

* Migrate unit/test_provides_kms_master_key.py from unittest to pytest

* Migrated unit/test/_providers_kms_master_key_provider.py from unittest to pytest

* unit/test_providers_raw_master_key.py

* Removed unit tests not corresponding to this branch

Author: ansanper

test/unit/test_providers_raw_master_key.py

@@ -11,8 +11,6 @@
 # ANY KIND, either express or implied. See the License for the specific
 # language governing permissions and limitations under the License.
 """Test suite for aws_encryption_sdk.key_providers.raw.RawMasterKey"""
-import unittest
-
 import pytest
 from mock import MagicMock, patch, sentinel
 
@@ -27,8 +25,9 @@
 pytestmark = [pytest.mark.unit, pytest.mark.local]
 
 
-class TestRawMasterKey(unittest.TestCase):
-    def setUp(self):
+class TestRawMasterKey(object):
+    @pytest.fixture(autouse=True)
+    def apply_fixtures(self):
         self.mock_algorithm = MagicMock()
         self.mock_algorithm.__class__ = Algorithm
         self.mock_algorithm.data_key_len = sentinel.data_key_len