minor #15417 Update bootstrap5.rst (abunch)

This PR was merged into the 5.3 branch.

Discussion
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Update bootstrap5.rst

Apply input-group class to a TextType field instead of a CheckboxType field

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Commits
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3a0dc3c Update bootstrap5.rst

Author: javiereguiluz

form/bootstrap5.rst

@@ -187,7 +187,7 @@ class to the ``row_attr`` option.
 
     .. code-block:: php
 
-        $builder->add('email', CheckboxType::class, [
+        $builder->add('email', TextType::class, [
             'label' => '@',
             'row_attr' => [
                 'class' => 'input-group',