Add flake8-bugbear to pre-commit.

tests/test_models.py

@@ -75,7 +75,7 @@ class AdminInterfaceModelsTestCase(TestCase):
         theme_4 = Theme.objects.create(name="Custom 4", active=True)
         theme_5 = Theme.objects.create(name="Custom 5", active=True)
         themes = [theme_1, theme_2, theme_3, theme_4, theme_5]
-        for i in range(5):
+        for _ in range(5):
             random.shuffle(themes)
             for theme in themes:
                 theme.set_active()

tests/test_multidb.py

@@ -1,4 +1,5 @@
 from django.test import TestCase
+from django.test.testcases import DatabaseOperationForbidden
 
 from admin_interface.models import Theme
 
@@ -22,7 +23,7 @@ class AdminInterfaceModelsWithDBRoutingTestCase(TestCase):
         assert db_for_theme == "replica"
 
     def test_dbrouter_errors_when_fetching_from_default(self):
-        with self.assertRaises(Exception):
+        with self.assertRaises(DatabaseOperationForbidden):
             Theme.objects.get_active()
 
     def test_dbrouter_fetches_db(self):