feat: get LANGUAGE_CODE from the environment variables

steering/settings.py

@@ -41,7 +41,8 @@ DATABASES = {
 }
 
 TIME_ZONE = os.getenv("TZ", default="Europe/Vienna")
-LANGUAGE_CODE = "de"
+LANGUAGE_CODE = os.getenv("LANGUAGE_CODE", default="en-us")
+
 USE_TZ = True  # django-oidc-provider needs timezones in database
 
 SECRET_KEY = os.getenv("SECRET_KEY", default="secret-key")