[#12802] Updated XML and PHP examples

Author: wouterj

security/form_login_setup.rst

@@ -341,6 +341,7 @@ a traditional HTML form that submits to ``/login``:
                     <guard>
                         <authenticator class="App\Security\LoginFormAuthenticator"/>
                     </guard>
+                    <logout path="app_logout" />
                 </firewall>
             </config>
         </srv:container>
@@ -360,6 +361,9 @@ a traditional HTML form that submits to ``/login``:
                             LoginFormAuthenticator::class,
                         ]
                     ],
+                    'logout' => [
+                        'path' => 'app_logout',
+                    ],
                 ],
             ],
         ]);