minor #20408 Replace annotation to attribute in form unit testing comment (alamirault)

This PR was merged into the 6.4 branch.

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Replace annotation to attribute in form unit testing comment

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a51974c Replace annotation to attribute in form unit testing comment

Author: javiereguiluz

form/unit_testing.rst

@@ -214,7 +214,7 @@ allows you to return a list of extensions to register::
         {
             $validator = Validation::createValidator();
 
-            // or if you also need to read constraints from annotations
+            // or if you also need to read constraints from attributes
             $validator = Validation::createValidatorBuilder()
                 ->enableAttributeMapping()
                 ->getValidator();