[Security]: Updating for new recipe

Page: https://symfony.com/doc/7.4/security.html

* I changed the regex to match the new recipe after symfony/recipes#1395
* I added the longer explanatory comment, as suggested at symfony/recipes#1395 (comment)

Author: ThomasLandauer

security.rst

@@ -31,7 +31,9 @@ creates a ``security.yaml`` configuration file for you:
             users_in_memory: { memory: null }
         firewalls:
             dev:
-                pattern: ^/(_(profiler|wdt)|css|images|js)/
+                # 'assets/' is for AssetMapper, 'build/' for Webpack Encore.
+                # (Note: no regex delimiters needed; Symfony adds `{}` automatically.)
+                pattern: ^/(_profiler|_wdt|assets|build)/
                 security: false
             main:
                 lazy: true