[Form] Removed Integer scale option

Scale option is hardcoded for IntegerType.
These changes result from the discussion introduced by
symfony/symfony#26734.

Author: dlabouesse

reference/forms/types/integer.rst

@@ -17,7 +17,6 @@ integers. By default, all non-integer values (e.g. 6.78) will round down
 | Rendered as | ``input`` ``number`` field                                            |
 +-------------+-----------------------------------------------------------------------+
 | Options     | - `grouping`_                                                         |
-|             | - `scale`_                                                            |
 |             | - `rounding_mode`_                                                    |
 +-------------+-----------------------------------------------------------------------+
 | Overridden  | - `compound`_                                                         |
@@ -47,8 +46,6 @@ Field Options
 
 .. include:: /reference/forms/types/options/grouping.rst.inc
 
-.. include:: /reference/forms/types/options/scale.rst.inc
-
 rounding_mode
 ~~~~~~~~~~~~~