minor #19098 Document twig functions on impersonation (94noni)

This PR was squashed before being merged into the 6.4 branch.

Discussion
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Document twig functions on impersonation

i am updating one of my app to 6.4 and also reading some https://symfony.com/blog/category/living-on-the-edge/7.0-6.4
found this was not yet documented
from https://symfony.com/blog/new-in-symfony-6-4-impersonation-utilities

edit: following code PR comment on Symfony-docs repo, found #18966
to me this is uselefull here as well as more "usage dev doc" instead of "TOC doc", wdyt?

FYO when googling "symfony user switch" the first link is the page I am proposing to edit

thx

Commits
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5c04c6b Document twig functions on impersonation

Author: OskarStark

security/impersonating_user.rst

@@ -70,6 +70,14 @@ as the value to the current URL:
 
     http://example.com/somewhere?_switch_user=thomas
 
+.. tip::
+
+    You can leverage the Twig function ``impersonation_path('thomas')``
+
+    .. versionadded:: 6.4
+
+        The ``impersonation_path()`` function was introduced in Symfony 6.4.
+
 .. tip::
 
     Instead of adding a ``_switch_user`` query string parameter, you can pass
@@ -128,6 +136,10 @@ To switch back to the original user, use the special ``_exit`` username:
 
     http://example.com/somewhere?_switch_user=_exit
 
+.. tip::
+
+    You can leverage the Twig function ``impersonation_exit_path('/somewhere')``
+
 This feature is only available to users with a special role called ``ROLE_ALLOWED_TO_SWITCH``.
 Using :ref:`role_hierarchy <security-role-hierarchy>` is a great way to give this
 role to the users that need it.