minor #18238 Adding link to main forms article (ThomasLandauer)

This PR was merged into the 5.4 branch.

Discussion
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Adding link to main forms article

Page: https://symfony.com/doc/5.4/form/without_class.html

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35cf2b7 Adding link to main forms article

Author: OskarStark

form/without_class.rst

@@ -2,8 +2,8 @@ How to Use a Form without a Data Class
 ======================================
 
 In most cases, a form is tied to an object, and the fields of the form get
-and store their data on the properties of that object. This is exactly what
-you've seen so far in this article with the ``Task`` class.
+and store their data on the properties of that object. This is what
+:doc:`the main article on forms </forms>` is about.
 
 But sometimes, you may want to use a form without a class, and get back an
 array of the submitted data. The ``getData()`` method allows you to do