Update deployment.rst

Corrected internal link.

Co-authored-by: Matthieu Lempereur <matt.lempereur@gmail.com>

Author: jdevinemt

deployment.rst

@@ -134,7 +134,7 @@ B) Configure your Environment Variables
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Most Symfony applications read their configuration from environment variables.
-While developing locally, you'll usually store these in `.env files <https://symfony.com/doc/current/configuration.html#configuring-environment-variables-in-env-files>`_. On production, you have two options:
+While developing locally, you'll usually store these in :ref:`.env files <configuration-env-var-in-dev>`. On production, you have two options:
 
 1. Create "real" environment variables. How you set environment variables, depends
    on your setup: they can be set at the command line, in your Nginx configuration,