bug #12240 remove extra ; from the code sample (slavchoo)

This PR was merged into the 4.3 branch.

Discussion
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remove extra `;` from the code sample

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Just a small fix of a typo

Commits
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01ca48b remove extra `;` from the code sample

Author: OskarStark

form/dynamic_form_modification.rst

@@ -452,7 +452,7 @@ The type would now look like::
                 ->add('sport', EntityType::class, [
                     'class'       => 'App\Entity\Sport',
                     'placeholder' => '',
-                ]);
+                ])
             ;
 
             $formModifier = function (FormInterface $form, Sport $sport = null) {