minor #9814 Fix missing use of IssueSelectorType (magnetik)

This PR was merged into the 2.8 branch.

Discussion
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Fix missing use of IssueSelectorType

Minor change, the use statement was probably a forgotten copy paste.

Commits
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c140ccc Fix missing use of IssueSelectorType

Author: javiereguiluz

form/data_transformers.rst

@@ -467,7 +467,7 @@ it's quite easy::
     // src/AppBundle/Form/Type/TaskType.php
     namespace AppBundle\Form\Type;
 
-    use AppBundle\Form\DataTransformer\IssueToNumberTransformer;
+    use AppBundle\Form\IssueSelectorType;
     use Symfony\Component\Form\Extension\Core\Type\TextareaType;
     // ...