add swagger docs to signin and signup endooints

services/backend/apps/users/apps.py

@@ -0,0 +1,9 @@
+from django.apps import AppConfig
+
+
+class UsersConfig(AppConfig):
+    default_auto_field = 'django.db.models.BigAutoField'
+    name = 'apps.users'
+    label = 'users'
+
+