erp5_web_renderjs_ui: html5_select: event option for notifyChange added. needs for determine event.type on parent gadget

i need it because use span for displaying icons in json form

It defaults to MAX_PARTITIONS, but if needed allows the caller to change the
amount of runs, especially in case if fine grained expectations are needed
from instantiation.

/reviewed-on nexedi/erp5!805