Add new flak8 rules to do some meaningful corrections

awx/main/migrations/_create_system_jobs.py

@@ -4,7 +4,7 @@ from django.utils.timezone import now
 
 logger = logging.getLogger('awx.main.migrations')
 
-__all__ = ['create_collection_jt', 'create_clearsessions_jt', 'create_cleartokens_jt']
+__all__ = ['create_clearsessions_jt', 'create_cleartokens_jt']
 
 '''
 These methods are called by migrations to create various system job templates

awx/main/migrations/_galaxy.py

@@ -44,7 +44,7 @@ def migrate_galaxy_settings(apps, schema_editor):
             credential_type=galaxy_type,
             inputs={'url': 'https://galaxy.ansible.com/'},
         )
-    except:
+    except Exception:
         # Needed for new migrations, tests
         public_galaxy_credential = Credential(
             created=now(), modified=now(), name='Ansible Galaxy', managed=True, credential_type=galaxy_type, inputs={'url': 'https://galaxy.ansible.com/'}