This update changes the icons used for pivot and list menu items in the spreadsheet editor to match Odoo's standard icons. The change also consolidates duplicate pivot and list insert menu items, improving the user interface consistency and reducing menu clutter.

This commit changes the icons of the pivot/list menu items to match the standard pivot/list icons of Odoo.

Task: [3559271](https://www.odoo.com/web#id=3559271&cids=1&menu_id=4720&action=333&active_id=2328&model=project.task&view_type=form)