[IMP] hr(_timesheet)_attendance: improvements for the ui

PURPOSE

Generic improvements for services.

SPECIFICATION

- For all reporting menus: removed the group by in the search view, and kept grouping
  the grid, pivot and graph views by the corresponding field.
- For timesheet/attendance, switched the pivot and graph views from their places.
- Renamed 'billable type' into 'billing type'.

task-2766164

closes odoo/odoo#85726

Related: odoo/enterprise#24940
Signed-off-by: Laurent Stukkens (ltu) <ltu@odoo.com>