Convert stats and related calls to async/await (#8192)

tests/storage/test_client_ips.py

@@ -16,13 +16,12 @@
 
 from mock import Mock
 
-from twisted.internet import defer
-
 import synapse.rest.admin
 from synapse.http.site import XForwardedForRequest
 from synapse.rest.client.v1 import login
 
 from tests import unittest
+from tests.test_utils import make_awaitable
 from tests.unittest import override_config
 
 
@@ -155,7 +154,7 @@ class ClientIpStoreTestCase(unittest.HomeserverTestCase):
         user_id = "@user:server"
 
         self.store.get_monthly_active_count = Mock(
-            return_value=defer.succeed(lots_of_users)
+            side_effect=lambda: make_awaitable(lots_of_users)
         )
         self.get_success(
             self.store.insert_client_ip(