fix: update header line

Author: Simperfit

components/console/helpers/questionhelper.rst

@@ -217,7 +217,7 @@ provide a callback function to dynamically generate suggestions::
     The ``setAutocompleterCallback()`` method was introduced in Symfony 4.3.
 
 Do not Trim the Answer
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~
 
 You can also specify if you want to not trim the answer by setting it directly with
 :method:`Symfony\\Component\\Console\\Question\\Question::setTrimmable`::