[Fixed] [Forms] rounding default const up to down

Author: Sébastien FUCHS

reference/forms/types/options/rounding_mode.rst.inc

@@ -1,7 +1,7 @@
 rounding_mode
 ~~~~~~~~~~~~~
 
-**type**: ``integer`` **default**: ``\NumberFormatter::ROUND_HALFUP``
+**type**: ``integer`` **default**: ``\NumberFormatter::ROUND_HALFDOWN``
 
 If a submitted number needs to be rounded (based on the `scale`_ option), you
 have several configurable options for that rounding. Each option is a constant