Added empty __init__.py module to tests package so that we can do

relative imports safely between test modules.

tests/test_recommendation_manager.py

@@ -1,6 +1,7 @@
 from taar.profile_fetcher import ProfileFetcher
 from taar.recommenders import RecommendationManager
 from taar.recommenders.base_recommender import BaseRecommender
+from .test_similarityrecommender import mock_s3_categorical_data   # noqa
 
 
 class MockProfileController:
@@ -60,7 +61,7 @@ def test_recommendation_strategy():
     assert results == EXPECTED_ADDONS
 
 
-def test_recommendation_ensemble():
+def test_recommendation_ensemble(mock_s3_categorical_data):
     """The recommendation manager support an ensemble
     method.  We want to verify that at least the dispatch
     to the stub ensemble recommendation is correctly executing.

tests/test_similarityrecommender.py

@@ -7,8 +7,8 @@ from moto import mock_s3
 from taar.recommenders.similarity_recommender import \
     CATEGORICAL_FEATURES, CONTINUOUS_FEATURES, S3_BUCKET, DONOR_LIST_KEY, LR_CURVES_SIMILARITY_TO_PROBABILITY, \
     SimilarityRecommender
-from similarity_data import CONTINUOUS_FEATURE_FIXTURE_DATA
-from similarity_data import CATEGORICAL_FEATURE_FIXTURE_DATA
+from .similarity_data import CONTINUOUS_FEATURE_FIXTURE_DATA
+from .similarity_data import CATEGORICAL_FEATURE_FIXTURE_DATA
 
 
 def generate_fake_lr_curves(num_elements, ceiling=10.0):