Remove superfluous "or not" [ci-skip]

Author: jonathanhefner

guides/source/configuring.md

@@ -1767,7 +1767,7 @@ Sets the host for the assets. Useful when CDNs are used for hosting assets rathe
 
 #### `config.action_controller.perform_caching`
 
-Configures whether the application should perform the caching features provided by the Action Controller component or not. Set to `false` in the development environment, `true` in production. If it's not specified, the default will be `true`.
+Configures whether the application should perform the caching features provided by the Action Controller component. Set to `false` in the development environment, `true` in production. If it's not specified, the default will be `true`.
 
 #### `config.action_controller.default_static_extension`