Update docs/infrastructure_and_maintenance/performance.md

Co-authored-by: Thorsten Reiter <[email protected]>

Author: dabrt

docs/infrastructure_and_maintenance/performance.md

@@ -56,7 +56,7 @@ In production setups:
 
     To avoid deprecations when using PHP 8.2 or 8.3, [= product_name =] v4.6.x needs an additional error handler.
     The error handler is present by default for projects that started with 4.6.8 or later.
-    For projects that started with earlier versions, you need to added the error handler manually by running the following commands:
+    For projects that started with earlier versions, you need to add the error handler manually by running the following commands:
 
     ``` bash
     composer config extra.runtime.error_handler "\\Ibexa\\Contracts\\Core\\MVC\\Symfony\\ErrorHandler\\Php82HideDeprecationsErrorHandler"