🚨(backend) fix linting issue

Fix linting issue in the backend codebase.

src/backend/core/models.py

@@ -11,8 +11,8 @@ from django.core import mail, validators
 from django.db import models
 from django.template.base import Template as DjangoTemplate
 from django.template.context import Context
-from django.utils.html import format_html
 from django.utils.functional import lazy
+from django.utils.html import format_html
 from django.utils.translation import gettext_lazy as _
 
 import frontmatter

src/backend/demo/tests/test_commands_create_demo.py

@@ -9,8 +9,6 @@ import pytest
 
 from core import models
 
-
-
 pytestmark = pytest.mark.django_db
 
 

src/backend/impress/settings.py

@@ -500,7 +500,7 @@ class Production(Base):
     #
     # In other cases, you should comment the following line to avoid security issues.
     # SECURE_PROXY_SSL_HEADER = ("HTTP_X_FORWARDED_PROTO", "https")
-    SECURE_PROXY_SSL_HEADER = ('HTTP_X_FORWARDED_PROTO', 'https')
+    SECURE_PROXY_SSL_HEADER = ("HTTP_X_FORWARDED_PROTO", "https")
 
     # Modern browsers require to have the `secure` attribute on cookies with `Samesite=none`
     CSRF_COOKIE_SECURE = True