Update system-configuration-overrides.md

small changes

Author: TomJaeger

docs/general/system-configuration-overrides.md

@@ -19,7 +19,7 @@ WARN: **Warning:** This article covers advanced topics.
 
 By default, ExpressionEngine's system settings are managed in the Control Panel and stored in the database, but these settings can be overridden with one of 3 configuration files: the main configuration file, the site index file, and the CP index file.
 
-You can also [set your own global variables](templates/globals/single-variables.md#custom-global-variables) in those files.
+You can also [set your own global variables](templates/globals/single-variables.md#custom-global-variables) in the above mentioned files.
 
 ##### Main configuration file