fixed problems related to optional modules

Author: Arfey

aiohttp_admin2/resources/__init__.py

@@ -1,7 +1,5 @@
 # flake8: noqa
 from aiohttp_admin2.resources.postgres_resource.postgres_resource import \
     PostgresResource
-from aiohttp_admin2.resources.mongo_resource.mongo_resource import MongoResource
-from aiohttp_admin2.resources.mysql_resource.mysql_resource import MySqlResource
 from aiohttp_admin2.resources.dict_resource.dict_resource import DictResource
 from aiohttp_admin2.resources.abc import Instance

tests/manager_fixtures.py

@@ -17,10 +17,10 @@
 
 from aiohttp_admin2.resources import (
     PostgresResource,
-    MySqlResource,
-    # MongoResource,
     DictResource,
 )
+from aiohttp_admin2.resources.mysql_resource.mysql_resource import MySqlResource
+# from aiohttp_admin2.resources.mongo_resource.mongo_resource import MongoResource
 
 
 resource_params = [