require APPLICATION_SETTINGS to be set

imaginaerraum_door_admin/__init__.py

@@ -78,7 +78,7 @@ def create_app():
     app.config.from_object(
         'imaginaerraum_door_admin.default_app_config.DefaultConfig'
     )
-    app.config.from_envvar('APPLICATION_SETTINGS', silent=True)
+    app.config.from_envvar('APPLICATION_SETTINGS')
 
     token_file = Path(app.config.get('TOKEN_FILE'))
     if not token_file.exists():