minor #8121 Use a safer code sample for Twig best practices (javiereguiluz)

This PR was merged into the 2.7 branch.

Discussion
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Use a safer code sample for Twig best practices

This fixes #7087.

Commits
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65bfd46 Use a safer code sample for Twig best practices

Author: xabbuh

best_practices/templates.rst

@@ -129,7 +129,7 @@ service in the constructor of the Twig extension:
                 new \Twig_SimpleFilter(
                     'md2html',
                     array($this, 'markdownToHtml'),
-                    array('is_safe' => array('html'))
+                    array('is_safe' => array('html'), 'pre_escape' => 'html')
                 ),
             );
         }