minor #12038 [Form] Mentioned the change in the "preferred choices" behavior (javiereguiluz)

This PR was squashed before being merged into the 4.4 branch (closes #12038).

Discussion
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[Form] Mentioned the change in the "preferred choices" behavior

Fixes #12023.

Commits
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aa2ceae [Form] Mentioned the change in the \"preferred choices\" behavior

Author: javiereguiluz

reference/forms/types/options/preferred_choices.rst.inc

@@ -3,9 +3,9 @@ preferred_choices
 
 **type**: ``array``, ``callable`` or ``string`` **default**: ``[]``
 
-This option allows you to move certain choices to the top of your list with a visual
-separator between them and the rest of the options. If you have a form of languages,
-you can list the most popular on top, like Bork Bork and Pirate::
+This option allows you to display certain choices at the top of your list with a
+visual separator between them and the complete list of options. If you have a
+form of languages, you can list the most popular on top, like Bork Bork and Pirate::
 
     use Symfony\Component\Form\Extension\Core\Type\ChoiceType;
     // ...
@@ -20,6 +20,12 @@ you can list the most popular on top, like Bork Bork and Pirate::
         'preferred_choices' => ['muppets', 'arr'],
     ]);
 
+.. versionadded:: 4.4
+
+    Starting from Symfony 4.4, the preferred choices are displayed both at the
+    top of the list and at their original locations on the list. In prior
+    Symfony versions, they were only displayed at the top of the list.
+
 This options can also be a callback function to give you more flexibility. This might
 be especially useful if your values are objects::