Clean-up warnings (#331)

Signed-off-by: Yuri Shkuro <[email protected]>

Author: yurishkuro

tests/test_crossdock.py

@@ -50,7 +50,7 @@ def app():
 
 
 # noinspection PyShadowingNames
-@pytest.yield_fixture
+@pytest.fixture
 def tracer():
     tracer = Tracer(
         service_name='test-tracer',

tests/test_reporter.py

@@ -96,7 +96,7 @@ def _incr_count(self, key, value):
 
 
 class ReporterTest(AsyncTestCase):
-    @pytest.yield_fixture
+    @pytest.fixture
     def thread_loop(self):
         yield