Update tag_whitelist.py

tracim/tracim/lib/email_processing/sanitizer_config/tag_whitelist.py

@@ -13,4 +13,4 @@ TAG_WHITELIST = [
     'samp', 'small', 'strong', 'sub', 'sup',
     'table', 'tbody', 'td', 'tfoot', 'thead', 'tr',
     'u', 'ul'
-]
+]