minor #20946 [Security] Update csrf.rst (Chris53897)

This PR was submitted for the 7.2 branch but it was merged into the 6.4 branch instead.

Discussion
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[Security] Update csrf.rst

i have no deeper knowledge. I just get over this while try to fixing problems with csrf

Please check with
https://symfony.com/doc/7.3/security.html#csrf-protection-in-login-forms

Commits
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347b1c1 Update csrf.rst

Author: javiereguiluz

security/csrf.rst

@@ -112,7 +112,7 @@ to do anything to be protected against CSRF attacks.
 
 .. _form-csrf-customization:
 
-By default Symfony adds the CSRF token in a hidden field called ``_token``, but
+By default Symfony adds the CSRF token in a hidden field called ``_csrf_token``, but
 this can be customized (1) globally for all forms and (2) on a form-by-form basis.
 Globally, you can configure it under the ``framework.form`` option: