minor #1137 adding logout_on_user_change parameter to main firewall (yassinechabli)

This PR was merged into the 3.4 branch.

Discussion
----------

adding logout_on_user_change parameter to main firewall

adding parameter **logout_on_user_change** to ignore the warning

Commits
-------

b9d4dc8 adding logout_on_user_change parameter to main firewall

Author: Tobion

app/config/security.yml

@@ -16,7 +16,7 @@ security:
         main:
             anonymous: ~
             # activate different ways to authenticate
-
+            logout_on_user_change: true
             # https://symfony.com/doc/current/security.html#a-configuring-how-your-users-will-authenticate
             #http_basic: ~