feat(src/djinit/templates/config/settings): add dj_database_url import and noqa directives

Add support for optional database URL configuration and silence import-related flake8 warnings.

- New Features: Introduce conditional import of `dj_database_url` in production settings.
- Enhancements: Suppress flake8 warnings for base imports using `# noqa: F401, F403`.
- Bug Fixes: None.

src/djinit/templates/config/settings/development.py-tpl

@@ -1,6 +1,6 @@
 """generated with djinit"""
 
-from .base import *
+from .base import *  # noqa: F401, F403
 
 SECRET_KEY = "[[ secret_key ]]"
 

src/djinit/templates/config/settings/production.py-tpl

@@ -1,6 +1,6 @@
 """generated with djinit"""
 
-from .base import *
+from .base import *  # noqa: F401, F403
 # @IF use_database_url
 import dj_database_url
 # @ENDIF