[FIX] web_editor: debounce we-range events

This commit allows to debounce the events of the RangeUserValueWidget so
that the user can use this widget with the left and right arrows without
having a lag effect (especially on the image quality option).

task-2601533

closes odoo/odoo#89040

Signed-off-by: Bojabza Soukéina (sobo) <sobo@odoo.com>