Update environment processor page

Replace file entries from ../* to %kernel.project_dir%/* to make it work in both console and in controllers.
See https://stackoverflow.com/questions/75409892/symfony-file-environment-variable-processor-not-working-in-console-command?noredirect=1#comment133062312_75409892

Author: redheness

configuration/env_var_processors.rst

@@ -399,7 +399,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(AUTH_FILE): '../config/auth.json'
+                env(AUTH_FILE): '%kernel.project_dir%/config/auth.json'
             google:
                 auth: '%env(file:AUTH_FILE)%'
 
@@ -440,7 +440,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(PHP_FILE): '../config/.runtime-evaluated.php'
+                env(PHP_FILE): '%kernel.project_dir%/config/.runtime-evaluated.php'
             app:
                 auth: '%env(require:PHP_FILE)%'
 
@@ -482,7 +482,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(AUTH_FILE): '../config/auth.json'
+                env(AUTH_FILE): '%kernel.project_dir%/config/auth.json'
             google:
                 auth: '%env(trim:file:AUTH_FILE)%'