minor #12353 Removed the symfony/security component (javiereguiluz)

This PR was merged into the master branch.

Discussion
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Removed the symfony/security component

Fixes #11989.

If you are a Symfony developer, don't worry. **We haven't removed the security component**, only the `symfony/security` "meta-package". This won't affect you in any way when using a full Symfony application. It only affects to people using that meta-package as a stand-alone package in a PHP application.

Commits
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65b84db Removed the symfony/security component

Author: javiereguiluz

components/security.rst

@@ -14,12 +14,6 @@ The Security Component
 Installation
 ------------
 
-.. code-block:: terminal
-
-    $ composer require symfony/security
-
-.. include:: /components/require_autoload.rst.inc
-
 The Security component is divided into several smaller sub-components which can
 be used separately:
 
@@ -38,6 +32,17 @@ be used separately:
     It brings many layers of authentication together, allowing the creation
     of complex authentication systems.
 
+You can install each of them separately in your project:
+
+.. code-block:: terminal
+
+    $ composer require symfony/security-core
+    $ composer require symfony/security-http
+    $ composer require symfony/security-csrf
+    $ composer require symfony/security-guard
+
+.. include:: /components/require_autoload.rst.inc
+
 .. seealso::
 
     This article explains how to use the Security features as an independent